Justice Moldaver wrote as follows (at paras. 1-4, 63-67, 78, 92-94, 97, 101, 155-157, 160-161):

"The trial process in Canada is one of the cornerstones of our constitutional democracy. It is essential to the maintenance of a civilized society. Trials are the primary mechanism whereby disputes are resolved in a just, peaceful, and orderly way.

To achieve their purpose, it is essential that trials be conducted in a civilized manner. Trials marked by strife, belligerent behaviour, unwarranted personal attacks, and other forms of disruptive and discourteous conduct are antithetical to the peaceful and orderly resolution of disputes we strive to achieve.

By the same token, trials are not — nor are they meant to be — tea parties. A lawyer’s duty to act with civility does not exist in a vacuum. Rather, it exists in concert with a series of professional obligations that both constrain and compel a lawyer’s behaviour. Care must be taken to ensure that free expression, resolute advocacy and the right of an accused to make full answer and defence are not sacrificed at the altar of civility.

...To be precise, was the Law Society Appeal Panel’s finding of professional misconduct against Mr. Groia reasonable in the circumstances? For the reasons that follow, I am respectfully of the view that it was not.

...Practicing law with civility brings with it a host of benefits, both personal and to the profession as a whole. Conversely, incivility is damaging to trial fairness and the administration of justice in a number of ways.

First, incivility can prejudice a client’s cause. Overly aggressive, sarcastic, or demeaning courtroom language may lead triers of fact, be they judge or jury, to view the lawyer — and therefore the client’s case — unfavourably. Uncivil communications with opposing counsel can cause a breakdown in the relationship, eliminating any prospect of settlement and increasing the client’s legal costs by forcing unnecessary court proceedings to adjudicate disputes that could have been resolved with a simple phone call.

Second, incivility is distracting. A lawyer forced to defend against constant allegations of impropriety will naturally be less focused on arguing the case. Uncivil behaviour also distracts the triers of fact by diverting their attention away from the substantive merits of the case. The trial judge risks becoming preoccupied with policing counsel’s conduct instead of focusing on the evidence and legal issues: Justice Michael Code, “Counsel’s Duty of Civility: An Essential Component of Fair Trials and an Effective Justice System” (2007), 11 Can. Crim. L.R. 97, at p. 105.

Third, incivility adversely impacts other justice system participants. Disparaging personal attacks from lawyers — whether or not they are directed at a witness — can exacerbate the already stressful task of testifying at trial.

Finally, incivility can erode public confidence in the administration of justice — a vital component of an effective justice system: Valente v. The Queen, [1985] 2 S.C.R. 673, at p. 689. Inappropriate vitriol, sarcasm and baseless allegations of impropriety in a courtroom can cause the parties, and the public at large, to question the reliability of the result: see Felderhof ONCA, at para. 83; Marchand (Litigation guardian) v. Public General Hospital Society of Chatham (2000), 51 O.R. (3d) 97, at para. 148. Incivility thus diminishes the public’s perception of the justice system as a fair dispute-resolution and truth-seeking mechanism.

...standards of civility must be articulated with a reasonable degree of precision. An overly vague or open-ended test for incivility risks eroding resolute advocacy. Prudent lawyers will steer clear of a blurry boundary to avoid a potential misconduct finding for advancing arguments that may rightly be critical of other justice system participants. In contrast, a standard that is reasonably ascertainable gives lawyers a workable definition which they can use to guide their behaviour. It also guides law society disciplinary tribunals in their task of determining whether a lawyer’s behaviour amounts to professional misconduct.

...

My colleagues in dissent interpret the “reasonable basis” requirement differently. In their view, the Appeal Panel concluded that where allegations of impropriety made against opposing counsel stem from a mistake of law, the mistake must be both honest and reasonable. And if the Appeal Panel determines that the mistake of law is unreasonable, even though it is honestly held, then the allegations of impropriety will not be reasonably based and can therefore lead to a finding of professional misconduct on account of incivility: Reasons of Karakatsanis J. et al., at paras. 193-96. In so concluding, they contend that my interpretation of the “reasonable basis” requirement — that allegations of impropriety must have a factual foundation, and not be based on innuendo or speculation — immunizes egregious legal errors from review, “effectively dispossess[ing] the law societies of their regulatory authority anytime a lawyer can cloak his accusations in a subjective legal belief”: reasons of Karakatsanis J. et al., at para. 221.

Respectfully, my colleagues’ concerns are misplaced. When a lawyer alleges prosecutorial misconduct based on a legal mistake, law societies are perfectly entitled to look to the reasonableness of the mistake when assessing whether it is sincerely held, and hence, whether the allegations were made in good faith. Looking to the reasonableness of a mistake is a well-established tool to help assess its sincerity: see e.g., Pappajohn v. The Queen, [1980] 2 S.C.R. 120, at p. 156, per Dickson J., dissenting, but not on this point; R. v. Bulmer, [1987] 1 S.C.R. 782, at p. 792; R. v. Moreau (1986), 26 C.C.C. (3d) 359 (Ont. C.A.), at pp. 374-75. The more egregious the legal mistake, the less likely it will have been sincerely held, making it less likely the allegation will have been made in good faith. And if the law society concludes that the allegation was not made in good faith, the second question — whether there was a reasonable basis for the allegation — falls away.

I pause here to note that there is good reason why a law society can look to the reasonableness of a legal mistake when assessing whether allegations of impropriety are made in good faith, but not when assessing whether they are reasonably based. The “good faith” inquiry asks what the lawyer actually believed when making the allegations. The reasonableness of the lawyer’s legal mistake is one piece of circumstantial evidence that may help a law society in this exercise. However, it is not determinative. Even the most unreasonable mistakes can be sincerely held.

...Allegations of professional misconduct or other challenges to opposing counsel’s integrity must be made in good faith and have a reasonable basis. Although a reasonable basis is not a high bar, I see no basis for interfering with the Appeal Panel’s conclusion that it is necessary to protect against speculative or baseless allegations.

...When considering the manner and frequency of the lawyer’s behaviour, it must be remembered that challenges to another lawyer’s integrity are, by their very nature, personal attacks. They often involve allegations that the lawyer has deliberately flouted his or her ethical or professional duties. Strong language that, in other contexts, might well be viewed as rude and insulting will regularly be necessary to bring forward allegations of prosecutorial misconduct or other challenges to a lawyer’s integrity. Care must be taken not to conflate the strong language necessary to challenge another lawyer’s integrity with the type of communications that warrant a professional misconduct finding.

...

The final contextual factor is the manner in which Mr. Groia brought his allegations. My colleagues assert that I “discount the manner in which Mr. Groia made his allegations”, thereby “setting a benchmark for professional misconduct that permits sustained and sarcastic personal attacks”: reasons of Karakatsanis J. et al., at paras. 211 and 227.

Respectfully, I take issue with that characterization of my reasons. I appreciate that a lawyer can be found guilty of professional misconduct for challenging opposing counsel’s integrity in an inappropriate manner. However, in this case, the manner in which Mr. Groia made his allegations could not, on its own, reasonably ground a finding of professional misconduct.

To be sure, Mr. Groia should not have made his allegations in the sarcastic tone that he sometimes employed. The tenor of his allegations at times descended into what can fairly be described as “petulant invective”: Felderhof ONSC, at para. 64. However, as indicated, throughout the majority of Phase One, the trial judge did not criticize Mr. Groia for the manner in which he was making his allegations. Although the trial judge’s passivity cannot be taken as acquiescence, it is nonetheless a relevant contextual factor to consider when evaluating the language and tone Mr. Groia chose to employ. When the trial judge did intervene, Mr. Groia appropriately modified the way in which he pursued his abuse of process arguments. The sarcastic manner in which Mr. Groia challenged the prosecutors’ integrity simply cannot, in light of the other contextual factors in this case, justify the Appeal Panel’s finding of professional misconduct.

...

Looking at the circumstances of this case as a whole, the following becomes apparent. Mr. Groia’s mistaken allegations were made in good faith and were reasonably based. The manner in which he raised them was improper. However, the very nature of Mr. Groia’s allegations — deliberate prosecutorial misconduct depriving his client of a fair trial — led him to use strong language that may well have been inappropriate in other contexts. The frequency of his allegations was influenced by an underdeveloped abuse of process jurisprudence. The trial judge chose not to curb Mr. Groia’s allegations throughout the majority of Phase One. When the trial judge and reviewing courts did give instructions, Mr. Groia appropriately modified his behaviour. Taking these considerations into account, the only reasonable disposition is a finding that he did not engage in professional misconduct.

I would allow the appeal and set aside the decision of the Appeal Panel with respect to the finding of professional misconduct against Mr. Groia and the penalty imposed. I would award costs to Mr. Groia in this Court and in the courts below, as well as in the proceedings before the Law Society. Because Mr. Groia, in the circumstances of this case, could not reasonably be found guilty of professional misconduct, the complaints against him are dismissed and there is no need to remit the matter back to the Law Society..."

Justices Karakatsanis, Gascon and Rowe in dissent wrote as follows (at paras. 175-177):

"We have read the reasons of our colleague Justice Moldaver and agree with him on a number of key issues. We agree that reasonableness is the applicable standard of review: Moldaver J.’s reasons (M.R.), at paras. 43–57. We also agree that the simple fact that a lawyer’s behavior [sic] occurs in the courtroom does not deprive the Law Society of Upper Canada of its legitimate role in regulating the profession nor does it justify heightened judicial scrutiny: M.R., at paras. 53–56. Lastly, we agree that, in articulating a standard of professional misconduct, the Law Society Appeal Panel reasonably set out a contextual approach which will vary according to the particular factual matrix in which it is applied: M.R., at paras. 77–80.

However, we disagree with Justice Moldaver’s disposition in this appeal. In our view, the Appeal Panel’s decision was reasonable. The Panel set out an approach for assessing whether Mr. Groia had committed professional misconduct and faithfully applied it. Its analysis was cogent, logical, transparent, and grounded in the evidence. Its decision achieved a reasonable balance of its statutory objectives and an advocate’s freedom of expression. There is no basis to interfere.

We also have a number of concerns about Justice Moldaver’s application of the reasonableness standard. Respectfully, we are of the view that he fundamentally misstates the Appeal Panel’s approach to professional misconduct, and reweighs the evidence to reach a different result. This is inconsistent with reasonableness review as it substitutes this Court’s judgment for that of the legislature’s chosen decision maker. Further, we have serious concerns about the impacts that will follow from our colleague’s analysis and disposition in this appeal."

Note: The summary and body are drawn from Eugene Meehan’s SupremeAdvocacy Weekly Updates for the Law Community.