Lawyers are governed by a comprehensive set of ethical rules which, when violated, often lead to civil liability regardless of the ethical violation (e.g., stealing from clients), but what impact does a rule violation have on legal malpractice or other claims against a lawyer?

Arizona's ethical rules contain the following Preamble:

Violation of a Rule should not itself give rise to a cause of action against a lawyer nor should it create any presumption in such a case that a legal duty has been breached. . . . . The Rules are designed to provide guidance to lawyers and to provide a structure for regulating conduct through disciplinary agencies. They are not designed to be a basis for civil liability. . . . .The fact that a Rule is a just basis for a lawyer's self-assessment, or for sanctioning a lawyer under the administration of a disciplinary authority, does not imply that an antagonist in a collateral proceeding or transaction has standing to seek enforcement of the Rule.Nevertheless, since the Rules do establish standards of conduct by lawyers, a lawyer's violation of a Rule may be evidence of breach of the applicable standard of conduct.

So, while the rules do not form the "basis for civil liablity," they canbeused to show "standards of conduct" and "a lawyer's violation . . . may be evidence of breach of the applicable standard of conduct." Accordingly, violations of ethical rules can be important factors in connection with any claim against an attorney and should be considered in addition to expert testimony as to the applicable standard of care.