Your list "12 Movies with Pivotal Lessons Featuring Lawyers," August, is fine, yet there is one remarkable omission and two surprising ones. The remarkable omission is Compulsion (1959), the roman à clef of the notorious Leopold and Loeb thrill-killing trial of 1924. In the film, the masterful Orson Welles plays the Clarence Darrow character, hired with the seemingly hopeless task of saving the necks of two privileged college "supermen" who killed a boy merely for the thrill of the act. Should the defense attorney put such an inflamed case before a judge or a jury? And how does he convince the trier not to hang such despicable killers? Darrow's famous closing argument as performed by Welles is a stunning legal moment—and lesson—in American film.
And it is surprising your list did not include A Civil Action (1998), the true story of how a lawyer's hubris can destroy his practice and injure his clients no matter how righteous the cause. Plus, any such list must include Witness for the Prosecution (1957), with its climactic cross-examination of the wife of the accused murderer, where the barrister as portrayed by the wily Charles Laughton shows how to use a piece of demonstrative evidence to trick the clever wife (Marlene Dietrich) into admitting something she had no intention of admitting.
Finally, as for the lesson of your aptly chosen Anatomy of a Murder (1959), you left out perhaps its greatest lesson—that the lawyer can win his client's case only to see him skip town without paying his well-earned fee.