November 01, 2019 Feature

Challenges in Responding to Mass Forensic Error

Bob Wicoff

How should the criminal justice system respond to mass error, where a serious issue is discovered that threatens to undermine many convictions?

Mass error takes many forms. One common example involves “bad actors,” regular participants in the system who are found to have engaged in such improper or even criminal behavior in one prosecution that a question naturally arises as to whether they engaged in similar misconduct in past cases. The most notorious example of this type of mass error was the Annie Dookhan situation in Massachusetts in 2011. Dookhan, a chemist at the state drug lab, was found to have engaged in drylabbing (visually identifying evidence samples as drugs without testing them) and other forensic nonconformance. Subsequent investigations into Dookhan’s misconduct cost Massachusetts more than $30 million and resulted in at least 21,000 drug convictions being vacated, the largest dismissal of wrongful convictions in US history. In 2013, Dookhan pleaded guilty and was sentenced to prison for obstruction of justice, perjury, and tampering with evidence.

Mass error involving bad actors is not confined to forensic science. In 2013, the Conviction Integrity Unit of the Brooklyn District Attorney’s Office ordered a review of 50 murder cases investigated by homicide detective Louis Scarcella, following mounting questions about that officer’s practices and the legitimacy of convictions in cases from the 1980s and 1990s. The Brooklyn prosecutor’s office has since requested that at least eight guilty verdicts involving Scarcella be vacated. (Sean Piccoli, Former Detective Is Confronted by Wrongfully Convicted Men, N.Y. Times, Apr. 2, 2019.)

A more challenging type of mass error involves changed or flawed science. As many commentators have pointed out, whereas the criminal justice system demands finality, science is always evolving, sometimes triggering retrospective case reviews to determine whether convictions based on scientific evidence should be revisited, where that science has evolved or been discredited. Most notably, the advent of DNA testing has rendered many other forensic disciplines (like ABO typing) obsolete in criminal cases or has relegated others to a minor supporting role (hair microscopy or fingerprint analysis), causing thousands of convictions to undergo renewed scrutiny. Reviews of cases involving DNA mixture evidence are underway in several states as a result of a scientific change in how probability statistics should be calculated regarding such evidence, and as more accurate software has become available for the task. Convictions have been revisited involving numerous other forensic disciplines that have undergone recent scrutiny, such as bite mark analysis, arson investigation, tool mark analysis (the comparison of impressions left on a fired bullet to a particular firearm), shaken-baby syndrome, comparative bullet lead analysis (the comparison of the chemicals found in bullets at crime scenes with ammunition found in the possession of a suspect), and bloodstain pattern analysis.

Mass forensic error has also occurred where well-intentioned experts, testifying about a valid scientific discipline, have overstated the probative value of such evidence. In 2013, prompted by three exonerations involving faulty hair microscopy evidence, the Innocence Project, NACDL, the FBI, and the Department of Justice collaborated on the Hair Microscopy Review Project, which investigated thousands of cases to determine whether forensic analysts had routinely exaggerated the extent to which microscopic hair analysis could serve as a “unique identifier” of the person who was the source of a hair found at a crime scene.

The discussion that follows focuses on the daunting challenges facing the criminal justice system in responding to mass forensic error due to a change in science or a realization that a scientific discipline was flawed. Some of these challenges are common to other types of mass error. However, in its scope and its complexity, mass forensic error faces added difficulty, and requires creative responses in conducting retrospective case reviews. As argued below, although the approach may differ depending on the nature and scope of the forensic issue that presents itself, the responsibility of managing both the notification and case review obligations are best entrusted to a state agency or some other centralized body, rather than relying on local prosecutors to notify affected persons in their jurisdiction, or appointing individual attorneys to review each case.

As with any other mass error, when there is a change in science or it is determined that a scientific method used in past criminal prosecutions is no longer valid, the criminal justice system is faced with two important obligations:

  1. Notification to Affected Persons: Difficult and unfamiliar questions face a prosecutor’s office when it is confronted with information that a forensic error or scientific change may have affected past convictions. First, does a prosecutor have any obligation to notify persons whose convictions were secured in part by forensic evidence that has now come under scrutiny? How can a prosecutor identify which convictions have been tainted by a forensic issue that may have touched thousands of cases stretching years in the past? Must there be actual notification to every affected person? How much detail is necessary in the notification letter itself? What are recipients told to do next?
  2. The Review Process: What is the most efficient way to conduct a large-scale review of hundreds or even thousands of convictions, especially when the problem involves a complicated scientific issue and spans many jurisdictions? Should every person whose conviction was touched by the problem be provided with his or her own attorney? Can the system provide enough attorneys who are competent in both the scientific issue at hand and post-conviction litigation? If the forensic issue that has come to light suggests retesting of evidence, how can forensic laboratories that are already inundated with pending cases bear such additional burden?

Notification by Prosecutors: An Inconsistent and Ineffective Response to Mass Forensic Error

Once a systemic forensic error is discovered, news of it typically winds its way from the lab to the prosecutor’s office, where the matter will either die or become the subject of some type of notification to those who may have been affected. In Texas, for example, forensic laboratories typically disclose an incident at their lab to the Texas Forensic Science Commission, the Texas Department of Public Safety (the statewide crime lab), and the appropriate national body that is responsible for the laboratory’s accreditation. The law enforcement agencies that submitted the evidence affected by the problem are also notified, as are the responsible prosecuting authorities. Although statewide defense lawyers’ associations or other stakeholders may be provided some general information about the problem, or may simply have become aware of it through the media or elsewhere, any actual notification to persons whose convictions were obtained with the help of the questioned evidence is left to the prosecutor because it is the prosecutor who generally bears the responsibility of notifying defendants when a conviction in that prosecutor’s jurisdiction may have been secured unfairly.

However, what follows (if anything) depends on the particular prosecutor, who as a threshold matter may have some understandable confusion as to what his or her notification obligation is in the post-conviction context. Despite statutes and ethical rules that suggest a continuing prosecutorial duty to notify convicted persons of exculpatory matters that have come to light, the reality is that to do so may be a daunting challenge, especially when the new information relates to changed science or other forensic nonconformance. Identifying the cases that may have been affected, especially when the forensic discipline at issue may have been used for many years, presents a difficult threshold problem, as does locating those defendants whose cases may have been resolved years earlier. If a prosecutor decides that the problem warrants actual notification, how much detail should be provided in the notification letter, and what are its recipients told to do? When these and other decisions regarding notification are left to each jurisdiction’s prosecuting authority, the nature and scope of any response may run the gamut, from no notification at all to an exhaustive and detailed letter being sent to every person affected. The challenge is formidable, and many prosecutors respond by doing nothing:

Many prosecutors—including well-intentioned ones—are subject to temptation to be less than ambitious in uncovering and disclosing past errors . . . the hortatory and ephemeral commandment to pursue justice is under terrific pressure when due diligence by a prosecutor would mean saddling herself and her colleagues the massive workload of relitigating or confessing error in thousands of convictions. The pressure is compounded by the fact that prosecutors’ ethical obligations concerning post-conviction evidence of innocence remain hazy, and that the institutional mechanisms by which such evidence should be communicated are ill-formed.

(Jennifer E. Laurin, The Massachusetts Lab Scandals: Confronting the New Normal of Mass Error in Criminal Justice, The Appeal (Oct. 10, 2017),

Whether to Notify: Does a Prosecutor Have Any Obligation?

Do prosecutors even have a duty to identify those convictions that might have been affected by a forensic problem or to notify the parties? There is no Brady obligation in the post-conviction setting. (Dist. Att’y’s Office for Third Judicial Dist. v. Osborne, 557 U.S. 52, 68–69 (2009).) State statutes may impose such a duty. (See, e.g., Tex. Code Crim. Proc. Ann., art. 39.14(h), (k) (requiring disclosure by the state of “any exculpatory, impeachment, or mitigating document, item, or information in the possession, custody, or control of the state . . . at any time before, during, or after trial”).) Additionally, as the US Supreme Court recognized in Imbler v. Pachtman, 424 U.S. 409, 427 n.25 (1976), prosecutors are “bound by the ethics of [their] office to inform the appropriate authority of after-acquired or other information that casts doubt upon the correctness of the conviction.” Rule 3.8(g) of the ABA Model Rules of Professional Conduct (“Special Responsibilities of a Prosecutor”) also imposes ethical duties in the post-conviction setting. Another indication that prosecutors increasingly recognize that their oath to seek justice extends to the post-conviction context is the advent of conviction integrity units. According to the National Registry of Exonerations, 33 conviction integrity units had been created in prosecutors’ offices nationwide by the end of 2017.

However, even those prosecutors who concede that there is a notification duty post-conviction might balk at the suggestion that they are generally obliged to apprise convicted persons of scientific changes, any more than they are obliged to notify convicted persons of new appellate opinions. Although, with respect to the “bad actor” category of systemic error (Annie Dookhan), the prosecutor’s duty to notify is clear, just as it would be if any other participant in the prosecution of the case had engaged in serious misconduct, the answer is not so obvious where forensic science has changed or come under other scrutiny. A large-scale notification effort is difficult and time-consuming. Prosecutors’ offices cannot be expected to provide actual notification every time they become aware of a change in forensic science. However, if flawed or changed science may have resulted in a wrongful conviction, there must be actual notification.

The following excerpt, from the written disclosure policy of the Harris County District Attorney’s Office Conviction Integrity Unit in Houston, suggests that the decision of whether to notify affected parties of any systemic issue, including changed science, may not lend itself to specific rules, but must instead be considered on a situation-by-situation basis:

Mass disclosure of information is appropriate where information potentially triggers a prosecutor’s duty to disclose [or] affects a large number of pending and/or disposed cases . . . Mass disclosure may be warranted when a condition, incident or an allegation of misconduct tends to affect the integrity of pending and/or disposed cases. Mass disclosure examples include, but are not limited to, the application of different standards for DNA mixture calculations due to scientific advancements, the destruction of property room evidence without court orders, non-controlled substance pleas, the lack of requisite legal policies at law enforcement agencies, and alleged false testimony by expert recurring government witnesses. [Emphasis in original.]

The policy then provides that the person with knowledge of information that may require mass disclosure will be responsible for conveying the information to a committee within the prosecutor’s office, which “will expeditiously review the information and make a recommendation on whether disclosure is necessary.” Credit should be given to any prosecutor’s office that undertakes to formulate a written notification policy, but as the excerpt makes clear, whether to proceed with mass disclosure is done on an ad hoc basis, turning on an assessment of whether a prosecutor’s duty to disclose is potentially triggered.

A retrospective review of thousands of cases involving DNA mixture evidence in Texas illustrates the risk of leaving it to each jurisdiction’s prosecutor to decide whether to notify convicted persons of a scientific change that may have impacted their case. The statewide review was begun in the state in 2015, after a potentially serious issue emerged regarding the scientific method that had been used to calculate the probabilities in cases involving DNA mixtures (where an item of evidence contains biological material from two or more contributors). The basic concern with the calculation method, called CPI (combined probability of inclusion), was that it may have mistakenly included individuals as possible contributors to DNA mixture profiles, where new, more precise calculations might yield inconclusive results, or even conclude that the individual was excluded as a contributor. (For more information on the DNA mixture issue, see DNA Mixture Analysis, Tex. Judicial Branch: Forensic Sci. Comm’n,

The DNA mixture issue was widely publicized in the criminal justice community in Texas. The Texas Forensic Science Commission posted a detailed notice of the problem on its website and notified the statewide prosecutors’ association, the Texas District and County Attorneys Association (TDCAA), which in turn sent notices to every elected prosecutor in the state. Through a grant from the Texas Indigent Defense Commission, a review group (whose statewide director is the author of this article) was formed with the task of reviewing any conviction upon request, to determine whether the forensic problem at hand might have compromised a conviction. Prosecutors were even provided a detailed form letter explaining the problem, to utilize in notifying persons whose cases might be affected, along with a form that the person could complete to request a review. However, despite repeated reminders to its members by TDCAA, as well as numerous appearances by review team members and forensic experts at continuing legal education conferences throughout Texas, by June 2019, as the review process had entered its fourth year, as many as half of the state’s prosecutors had not issued any notification of the problem to affected persons. Such lukewarm response may be attributable in part to there being no eligible cases in some rural counties, leaving those prosecutors with nothing to disclose. However, given the crime laboratories’ estimates of the number of cases that have been touched by the DNA mixture problem, it is clear that some prosecutors simply concluded that they had no obligation to notify anyone or simply did not want to make the effort.

How to Notify: Difficulties Facing Prosecutors Who Undertake Mass Disclosure

Prosecutors who decide to issue mass disclosures in response to a systemic forensic issue face numerous challenges.

Identifying the affected cases. A threshold difficulty is that it is not always easy to identify the cases that may have been affected by a forensic problem. For example, the CPI method that prompted the DNA mixture review in Texas was used to calculate DNA probability statistics in prosecutions spanning 20 years. The recently discovered concern with CPI was unforeseen at the time the calculation was being used; neither the laboratories nor the prosecutors were carefully categorizing which cases used the method, as there was no reason to do so at the time. As a result, once the CP. method came under scrutiny, it was a daunting task to identify which convictions, among the thousands that had involved DNA mixture evidence over two decades, had utilized the now-scrutinized CPI method.

As a result, most prosecutors who have opted to notify convicted persons of the CPI issue have cast a wide net of notification. In some counties in Texas, for example, prosecutors sent notice letters in every case where the police offense report contained the entries “DNA” or “mixture,” or in every case where the crime lab identified a DNA mixture, but without determining whether CPI was also involved. Such overreaching resulted in thousands of persons receiving a letter notifying them that there may be a forensic issue that affected their case, when in fact their case had no such issue at all. In great part, such an overreaching approach to notification was born of a concern among prosecutors that speed was of the essence, that notification could not wait for a methodical search through “possibly affected” cases to identify the “definitely affected” cases. Understandably, no prosecutor wanted to be viewed as sitting on his or her hands with regard to a serious forensic problem, in the event someone in prison was found to deserve a new trial due to the CPI issue. However, in addition to such approach resulting in untold hours of unnecessary work for both prosecutors and attorneys working on the subsequent review of cases, as well as creating delays in reaching anyone whose conviction may in fact have been undermined by CPI, there has been an undesired human cost: Many inmates and others desperate to escape the effects of their convictions were given false hope that there might be some problem with their conviction, when the forensic method in question was not even used in their case.

Locating persons affected by the problem. Notifying thousands of persons of an issue that may have affected their case is a daunting logistical challenge, especially in cases that were finalized years ago and for which the defendants are no longer incarcerated or on parole. Even the most exhaustive notification effort should be accompanied by every available type of constructive notice, such as repeatedly providing information through the media. An added problem with actual notification is that many convicted persons may choose to avoid or even discard a letter from the same agency that had prosecuted them, reasoning that it can’t be good news. Sending a copy of the notification letter to the last attorney of record for the convicted person might get a slightly better response, but the unfortunate reality is that many attorneys, believing that their obligations have ended once their client’s case has been concluded, view such a notification letter as something that is no longer their problem. At the same time, many convicted persons, seeing that a copy of the letter had been sent to their last attorney of record, might assume that the matter is therefore being investigated by the attorney. At the outset of the Texas DNA Mixture Review, in a well-intentioned attempt to reach the greatest number of affected persons possible, letters explaining the forensic problem were even posted in prison law libraries throughout the state, an approach that had an undesired result: hundreds of requests for review from inmates whose convictions had nothing whatsoever to do with DNA.

The contents of the notice letter. A notification letter sent to the convicted person needs to serve the dual purpose of informing that person of the forensic issue that is involved, in terms that a layperson would understand, and providing that person with the contact information for someone who can provide further help. Unfortunately, when the content of disclosure letters is left to each jurisdiction’s prosecutor, notification becomes inconsistent and sometimes obscure, such as a notice letter issued by one prosecutor’s office in Texas in 2015, which cryptically informed its recipients that “certain witnesses in your case may have serious credibility issues that possibly affected the outcome of your case.” If that piece of news is not confusing enough, what the recipient is then told to do with such information borders on sarcasm: “take whatever action you deem necessary.” In a jurisdiction without a public defender’s office or some other obvious resource, what step would a prison inmate take next: contact his convicting court, write an innocence clinic, draft his own post-conviction writ?

A Better Approach to Notification: Centralizing the Responsibility

A more consistent and effective approach to mass disclosure of systemic issues would be to create a centralized agency for the task. It is worth considering whether, as a matter of instilling confidence in the system, it makes sense to let the very office that prosecuted the case decide whether to notify convicted persons that there is now a question as to the conviction’s validity. As explained above, entrusting the notification decision to each jurisdiction’s prosecutor creates inconsistent results. A better approach would be the establishment of an independent state notification entity, either standing alone or as part of an existing agency, charged with the responsibility to assess errors (both forensic and otherwise) that are reported to it by stakeholders in the system, or which the agency becomes aware of independently, and to make decisions regarding notification according to specific policies. Many prosecutors would likely welcome such an independent agency, which would not only absolve them of the responsibility of deciding when they are required to issue mass disclosures or how quickly they must accomplish the task but would also preserve their resources.

Virginia provides a possible model of a statewide notification system. In 2008, as part of an effort to review over 3,000 old criminal cases that might benefit from DNA testing, the state established a DNA Notification Subcommittee, which was tasked with identifying and notifying those individuals whose case files were found to have suitable biological evidence. (For more information on the Virginia State Crime Commission DNA Notification Project, see Va. State Crime Comm’n, Overview of DNA Notification Project (Sept. 23, 2014), Although the Virginia notification committee was formed as an ad hoc response to a single forensic issue, it reveals obvious benefits in establishing an independent centralized agency to report mass errors:

Policy decisions, such as which types of cases qualify for notification, are not left to the discretion of the prosecutor whose conviction is now under scrutiny, and who may or may not recognize a duty to notify, but are instead determined by a group consisting of various stakeholders in the system, including defense attorneys, forensic analysts, prosecutors and law enforcement officers.

The mechanics of notification, such as the method of notification that is used or the contents of a mass disclosure letter, are determined according to rules and after discussion and voting by agency members, rather than arbitrarily, according to the unfettered discretion of each jurisdiction’s prosecutor.

A recognized state notification agency would be able to work more seamlessly with other state agencies and volunteer groups that would assist in the task of identifying affected cases and locating individuals, such as the state department of motor vehicles, court clerks, pro bono attorneys, law school volunteers, and crime laboratories.

An independent notification agency would likely elicit a better response from those persons receiving notice than if the notice were sent by the office that had prosecuted them.

The added cost of such a notification entity would be offset by money saved at the local level, as prosecutors’ offices are relieved of the cost of mass notification efforts.

Providing Case Reviews to Persons Affected by Mass Forensic Error

As stated above, the contents of any notification letter must not only explain the problem that has been discovered but should also refer the recipient to someone who can help. Moreover, as a matter of fundamental fairness, because the convicted person bears none of the blame for the systemic error that has visited his or her case, the criminal justice system should provide an effective means of review, irrespective of that person’s financial resources. However, where the problem at hand is a systemic error that affects many convictions over multiple jurisdictions, such as changed or flawed science, and there is no obvious source (such as a statewide public defender’s office) to refer people to, it is not clear who inmates and other affected persons should be told to contact.

Appointment of habeas counsel. Although various state laws may provide for the appointment of habeas counsel, there is no constitutional right to counsel in habeas proceedings. (Pennsylvania v. Finley, 481 U.S. 551 (1987).) The matter is typically left to the discretion of each court. In any event, the appointment of counsel on a case-by-case basis is an ineffective and costly approach to conducting a large-scale review following an outbreak of mass error. This is especially true when the error involves some arcane matter of forensic science.

First, if a forensic problem has resulted in a large number of notifications issued over a short span of time, there arises an immediate need to find available attorneys who are competent in post-conviction habeas litigation and who can be trained in the forensic issue at hand. As to the first requirement, as a general proposition, relatively few attorneys have experience in post-conviction habeas litigation, especially in less-populated counties. As for the forensic training, some forensic issues prove very difficult for attorneys to learn, even at a rudimentary level, despite the vast amount of information that is available on the Internet and any training offered by the forensic community. It often takes repeated exposure to become “fluent” in a forensic problem. Does it make sense for a county to pay for a number of attorneys to spend substantial time becoming educated about a novel scientific issue, where each attorney may only be appointed to a handful of cases? Additionally, even if enough skilled attorneys can be summoned for the task, the overall case review is hampered as the number of attorneys who are involved increases. In reviewing a case that has seen a forensic error, an attorney would typically find it necessary to interact with various agencies, such as conviction integrity units, forensic laboratories, and clerk’s offices that maintain transcripts and other records. The quality of the overall case review suffers from the congestion caused by a large number of attorneys interacting with these groups individually, each pursuing his or her handful of cases in a different way, at a different pace, and with a different level of experience in habeas corpus litigation or understanding of the scientific issue that is involved. Simply, as discussed below, an effective review of thousands of cases is best accomplished by one centralized group, which benefits by repeated exposure to the systemic issue at hand, and which can more seamlessly interact with the various agencies involved in the review process.

Another problem with the appointment of individual attorneys to review cases is that in many instances, it turns out that the case did not warrant the appointment of counsel to begin with. As explained above, many mass disclosure efforts, hampered by the inherent difficulty in identifying those cases that may be affected by a forensic error, err on the side of extreme caution by sending notification letters to many persons whose case was entirely devoid of the problem. If recipients of notice letters are advised to contact their convicting court, which in turn appoints habeas counsel, it is inevitable that many cases that did not have any problem, but made the notification list anyway, will be provided a court-appointed attorney, with a certain amount of activity sure to follow. Attorneys’ fees will inevitably accumulate as appointed attorneys, trying to do their due diligence, begin to familiarize themselves with the unique process necessary in reviewing a case beset by a forensic error: educating themselves about the science involved, learning how to read a lab report, communicating with the client to explain more about the issue, making contacts with the appropriate personnel at crime laboratories, requesting old case records, and researching the applicable law. Just as many prosecutors err on the side of caution in their notification efforts, sending many more notifications than necessary due to a sense of urgency and uncertainty about which cases are eligible, so too there is often a tendency on the part of well-meaning attorneys who are appointed to these cases to proceed aggressively. In the “age of innocence,” highlighted regularly by new DNA exonerations or novel forensic error, some urgency naturally accompanies the representation of a client, especially when that client is incarcerated, who has received notice from a prosecutor that his or her conviction may have been undermined by a forensic error.

The problem, as stated earlier, is that many cases should never have gotten to the point of notification, either because the problematic forensic method that has come to light was not used in the case or because it is immediately apparent that the presenting problem could not conceivably have compromised the conviction. As discussed below, appointing individual attorneys to these cases should come at a later point in the overall case review process, after there has been an initial screening of cases to determine both the existence of the forensic error and a determination that the error could have affected the conviction. This review is best done by a centralized group of attorneys.

Referral to innocence projects and other volunteer groups. Suggesting that recipients of a notification letter contact an innocence project, a law school clinic, or even the pro bono section of a civil firm is even more problematic. For one thing, as stated above, it is the criminal justice system’s responsibility to provide assistance in investigating a problem that was of the system’s making. Although these volunteer groups can play an important role in a larger review effort, the system itself must provide a response to a systemic problem; referral to volunteer groups shirks that responsibility. Innocence projects are typically overwhelmed with cases. Law school clinics have an abundance of enthusiasm and energy but are typically ill-equipped to provide assistance in a matter as arcane as post-conviction habeas litigation and rely on students who may only work on a case for the semester. Civil firms sometimes provide the best representation a criminal defendant could hope to have, but the number of persons they can help is obviously limited and referring large numbers of inmates or other affected persons to a civil firm would be inappropriate for several other obvious reasons.

One State’s Approach to Retrospective Case Review: The Texas DNA Mixture Review Project

In 2015, stakeholders from the criminal justice community in Texas convened to discuss how to best handle the looming DNA mixture problem, which it was believed had the potential of undermining many convictions throughout the state. The statewide crime lab, the Texas Department of Public Safety, estimated that the forensic method in question, CPI, had been used in its labs in approximately 25,000 cases over roughly 15 years, and that various other crime laboratories in Texas had probably used the same method in an equal number of prosecutions. Because Texas does not have a statewide public defender’s office, various other approaches to notification and case review were considered. For example, one suggestion for a retrospective case review was that inmates and other affected persons should be advised to seek a review of their case by filing a motion with their convicting court, pursuant to the state’s post-conviction DNA testing statute, which provided for appointment of counsel. This was a less-than-perfect solution, however. The statute provided for post-conviction DNA testing under certain specified conditions, not for a review of testing that had already taken place. Additionally, the prospect of paying for court-appointed attorneys in thousands of post-conviction cases was clearly not an optimal solution.

It was finally decided that the responsibility for providing retrospective case reviews was best placed in a review group, later to be called the Texas DNA Mixture Review Project, which would be staffed by an assistant public defender from Houston and several contract attorneys throughout the state, and funded by a grant from the Texas Indigent Defense Commission. The Texas Forensic Science Commission prepared a notification letter for prosecutors throughout the state to send to inmates and other affected persons who had been convicted in their county. The letter explained the nature of the forensic problem and provided recipients with the contact information for the mixture review project, along with a form that could be sent back to the project to request a review of the case.

The DNA mixture review group obtains necessary court documents from trial cases (such as appellate opinions or trial transcripts) and guilty plea cases (offense reports) and also obtains any necessary data from crime labs, all toward the end of determining whether the forensic issue was present in the case and could have been material to that conviction. The client is also provided a lengthy information sheet to complete and return to the review group. In those cases that involve the disputed forensic method, if the DNA evidence is even arguably material to the conviction, the labs are asked to do new calculations according to updated methods. If there is a significantly better result from the recalculation, then the review team refers the matter to the convicting court for appointment of habeas counsel. If it is determined that the DNA evidence in the case could not possibly have been material to the conviction, or that the review should not continue for other reasons, the client is sent a detailed letter explaining the decision. The client is also told that the decision of the project has no binding legal effect, and that a request may still be made of the convicting court to appoint counsel.

Such a centralized review group enjoys many advantages over the appointment of an attorney to each case:

Through training and repeated exposure to lab reports and access to forensic experts, the project’s attorneys have become very knowledgeable about the forensic issues that are involved, to the extent that they are a resource for other attorneys who may be dealing with the same forensic issue. Thus, whereas the appointment of each new court-appointed attorney would require training in the forensic issue involved, the project’s attorneys are already familiar with the science.

Recognized as a state-supported review group, the project has availed itself of motivated volunteer lawyers, from both the criminal justice community and the pro bono sections of civil firms, as well as law students and retired attorneys, to assist in the project. The project trains these volunteers, assists them along the way, and provides a second opinion about the resolution of each case.

The project has worked with crime laboratories around the state to develop a procedure whereby the labs do an initial search of cases to determine whether the forensic issue is even present in the case, thereby preventing time needlessly spent on cases that may have received notification in error. Through this procedure, no time is spent on evaluating a case unless the lab first reports that the case qualifies for review.

The project has also established a streamlined protocol with conviction integrity units and other prosecutors for producing offense reports for the purpose of reviewing the effect of the forensic problem in guilty plea cases.

The project has established a procedure with appellate courts and district clerks throughout the state to procure trial transcripts and other court records that are necessary to conduct case reviews.

The repeated contact that has been necessary between lab personnel, prosecutors, and project attorneys has resulted in a working relationship that has facilitated case reviews.

The Texas Forensic Science Commission, which often receives formal requests for case reviews from inmates and other persons regarding DNA issues in their case, regularly refers people to the project for help.

Having now reviewed over 3,000 cases in response to requests for review, the project has cost a fraction of what would have been spent if attorneys had been appointed on a case-by-case basis.

During the preliminary discussion of the creation of the mixture review project, a question was raised as to whether there was any point in establishing a review group whose findings had no binding legal effect, the concern being that anyone who disagreed with the project’s conclusions would simply seek a court-appointed attorney or pursue other options. Interestingly, this has not been the case. Almost without exception, in those cases where the project has concluded that a particular case review should end without referral to the court for appointment of habeas counsel, the client has taken no further steps seeking review, in part because each client is provided with a full explanation, often in the form of a multipage memorandum, explaining the reasons that the project has concluded that the case does not qualify for further review.


As with any pending storm, preparation is essential. Mass error, in whatever form, will only become more common, as forensic science continues to evolve and as prosecutors increasingly recognize a post-conviction duty to disclose systemic errors that may have undermined past cases. It is essential that stakeholders in the criminal justice system work together to create efficient and cost-effective institutional responses that can be applied to each new outbreak of injustice.


Bob Wicoff is an assistant public defender at the Harris County Public Defender’s Office in Houston, Texas, and is the director of the Texas DNA Mixture Review Project.