No doubt about it, disputes and litigation between opposing parties can induce high levels of stress, sometimes resulting in the lawyers involved engaging in trial tactics or other behavior that they later come to regret (one would hope) and would rather forget. Although the Rules of Professional Conduct permit lawyers to represent their clients zealously, there are limits as to what is deemed to be acceptable.
A Brief History of Zeal
Efforts to circumscribe the limits of zealous representation have been a constant in the development of legal ethics standards. In the 1908 ABA Canons of Professional Ethics, Canon 15 stated: “a lawyer owes entire devotion to the interest of the client, warm zeal in the maintenance and defense of his rights and the exertion of his utmost learning and ability”. In the Model Code of Professional Responsibility that was adopted in 1969 and replaced by the Model Rules of Professional Conduct in 1983, the modifier “warm” was dropped. See, Canon 7. Ethical Considerations 7-37 and 7-38 also provided the following guidance:
In adversary proceedings, clients are litigants and though ill feeling may exist between clients, such ill feeling should not influence a lawyer in his conduct, attitude, and demeanor towards opposing lawyers. A lawyer should not make unfair or derogatory personal reference to opposing counsel. Haranguing and offensive tactics by lawyers interfere with the orderly administration of justice and have no proper place in our legal system.
A lawyer should be courteous to opposing counsel and should accede to reasonable requests regarding court proceedings, settings, continuances, waiver of procedural formalities, and similar matters which do not prejudice the rights of his client. He should follow local customs of courtesy or practice, unless he gives timely notice to opposing counsel of his intention not to do so. A lawyer should be punctual in fulfilling all professional commitments.
ABA Model Rule 1.3 Diligence addresses the bounds of zealous representation. See the following excerpts from paragraph  of the Comment to Rule 1.3:
…A lawyer must also act with commitment and dedication to the interests of the client and with zeal in advocacy upon the client's behalf. A lawyer is not bound, however, to press for every advantage that might be realized for a client. … The lawyer's duty to act with reasonable diligence does not require the use of offensive tactics or preclude the treating of all persons involved in the legal process with courtesy and respect.
This last sentence of the above comment was added pursuant to the ABA Ethics 2000 Commission’s (E2K) recommended amendments to the Model Rules. The E2K’s Reporter’s Explanation of Changes memorandum on Rule 1.3 state:
… and  New material has been added to comments  and  to provide some support for the bar's civility initiatives. No change in substance is intended.
For a discussion of the historical origins of the concept of zeal in professional ethics standards for lawyers, See, Lawrence J. Vilardo, Vincent E. Doyle III,. Where Did the Zeal Go? Litigation, Volume 38, Number 1, Fall 2011.
Rules 3.4, 3.5, 4.4 and 8.4(d)
Other Rules of Professional Conduct including 3.4 Fairness to Opposing Party and Counsel, 3.5 Impartiality and Decorum of the Tribunal and 4.4 Respect for Rights of Third Persons and 8.4(d) Misconduct: conduct prejudicial to the administration of Justice are also implicated when lawyers engage in conduct that exceeds the accepted limits of zealous representation. For further information on the application of these Rules, see the annotations to them as they appear in the eighth edition of the ABA Annotated Model Rules of Professional Conduct (2015).
Civility and Professionalism Standards
Beyond the applicable rules of professional conduct, many state and local bar associations have adopted civility or professionalism codes and creeds for lawyers. For a list of these codes, oaths, and creedsSee, the ABA Center for Professional Responsibility Standing Committee on Professionalism’s webpagethat posts links to many of them. See, for example the Principles of Professionalism for Delaware Lawyers that states as follows:
…A lawyer should represent a client with vigor, dedication and commitment. Such representation, however, does not justify conduct that unnecessarily delays matters, or is abusive, rude or disrespectful. A lawyer should recognize that such conduct may be detrimental to a client’s interests and contrary to the administration of justice.
Case Law and Ethics Opinions
Cases and ethics opinions address a wide variety of conduct that has been found to have violated Rules 3.4, 3.5, 4.4 and 8.4(d).
Recent cases include In re Eisenstein, 2016 WL 1357206, 2016. In Eisenstein, the Missouri Supreme Court found that a lawyer’s attempt to silence opposing counsel with a threatening email over his client’s unauthorized removal of personal information including trial strategy from his wife’s computer coupled with his failure to notify opposing counsel that he had received the information constituted violations of Rules 4.4 and 8.4(d) (conduct prejudicial to the administration of justice) warranting a six month suspension. His email to opposing counsel read: “Rumor has it that you are quite the gossip regarding our little spat in court. Be careful what you say. I'm not someone you really want to make a lifelong enemy of, even though you are off to a pretty good start. Joel.” The court found that his e-mail constituted a threat that there would be professional retribution if she discussed the matter. In California, a lawyer defending a client against a claim of police brutality for unlawful arrest and excessive force went on the offensive with an email saying “if he sets foot in California, …there is a very real chance he will be arrested. We intend to have both federal and state law enforcement present during the trial.” The basis for the threat was the defendant’s alleged drug use, which if established, would open the potential for legal action. The lawyer for the claimant moved to disqualify the defense counsel for making a threat of a criminal charge to gain advantage in a civil matter. Disqualification was not granted, but the judge ordered the defense lawyer not to have the plaintiff arrested or otherwise interfere with the trial. Lopez v. Banuelos, 2013 WL 4815699.
In In re Holste, 358 P.3d 850 (Kan. 2015), a part-time county attorney violated Kansas Rules 8.4(d) and 4.4(a) when he misused his official status to threaten criminal action to benefit his client's position in a civil lawsuit. The Kansas Supreme Court suspended the lawyer for a period of two years with leave to re-apply after six months, taking note of the lawyer’s misuse of his official status when increasing sanction from the recommended published censure. In In re Nathan, Minn., 671 N.W.2d 578 (2003) the Minnesota Supreme Court imposed an indefinite suspension on a lawyer who threatened and harassed numerous people involved in his cases. In a child visitation matter the lawyer sent the guardian ad litem harassing letters in which he called her “worse than worthless” and threatened to publish the guardian ad litem's letters on his Web site. In another matter, the same lawyer represented a mother in a proceeding to terminate her parental rights. Nathan sent a threatening letter to the psychologist hired by the county and also harassed the social worker in the case, calling her “out-of-control,” “power crazed,” and racist.
The judge levied $1,500 in sanctions against Nathan, and issued a protective order directing him not to make any part of the case public without prior court permission.
In Fla. Bar v. Diaco, 2016 BL 23619, Fla., No. SC14-1052, 1/28/16, unpublished, lawyer Diaco was permanently disbarred after he plotted an eloborate scheme to have opposing counsel arrested for DUI. In this case, lawyers for the plaintiff conspired with their paralegal to flirt with opposing counsel, encouraging him to drink to excess and then to drive home all the while alerting the police to arrest him for driving under the influence.
In In Re Coe No. 01-2488-D, 7/16/03, the Wisconsin Supreme Court admonished lawyer Coe for being sarcastic and disrespectful toward the disciplinary referee. The lawyer’s disrespectful comments included saying the referee's “patent and reprehensible masquerade of fairness” was “an embarrassment to the history of jurisprudence.” And that the referee was “nothing but a cheerleader for the OLR,” and “the referee, in an attempt to keep the gross injustice of this case in the dark, conveniently kept his intellectual light bulb turned off.” Coe also described the referee's “antebellum condescension” and referred to one of the referee's comments as “a rare moment of intellectual activity”
The court found that Coe's “excessive sarcasm and hyperbolic rhetoric are unbecoming to a lawyer, and undermine the decorum and integrity of the judicial process”.
When representing clients, bear in mind the last sentence of paragraph 1 of the Comment to Rule 1.3 that is quoted earlier in this article but that bears repeating:
…The lawyer's duty to act with reasonable diligence does not require the use of offensive tactics or preclude the treating of all persons involved in the legal process with courtesy and respect.
Conduct that is disruptive of court proceedings or that is disrespectful of the participants in the matter can sometimes cross the line. As always, for further guidance check the local rules of professional conduct, ethics opinions and case law of the jurisdiction. Your state or local bar may also be able to help.