ABA Model Rules of Professional Conduct, Rule 8.4: Misconduct: "It is professional misconduct for a lawyer to: [...] (c) engage in conduct involving dishonesty, fraud, deceit or misrepresentation..."

[https://www.americanbar.org/groups/professional_responsibili...]

If it really was intentional, this very clearly meets the standard, and there's absolutely no requirement that there be damages for the lawyer to be disciplined. I'm not talking about a fraud or malpractice claim, so there's no reason this would involve a lengthy court battle, etc.

Further, Rule 8.3: "(a) A lawyer who knows that another lawyer has committed a violation of the Rules of Professional Conduct that raises a substantial question as to that lawyer's honesty, trustworthiness or fitness as a lawyer in other respects, shall inform the appropriate professional authority."

[https://www.americanbar.org/groups/professional_responsibili...]

Seems to fit as well if the behavior was repeated.