Let's begin with a five page story featuring Betty Bates, Lady at Law. Betty Bates was created by Stanley Charlot (a pen name of artist Bob Powell) and this story was illustrated by Nick Cardy. It debuted as the second story in Hit Comics #5, an anthology book put out in November 1940 by Quality Comics. 

The Jerry Corona casefile, presented above, is actually Ms. Bates' second story. She debuted in Hit Comics #4 in October of 1940. A Betty Bates story would appear in every issue of Hit Comics until the book folded with issue #65 in 1950. That's 59 comics over a period of ten years. As far as I can tell, that's the longest consecutive run any comic book lawyer would have until Matt Murdock put up his shingle over at Marvel Comics as Daredevil in 1964.

Betty Bates was as tough as they come. She began stories as a defense attorney for hire but moved on to become a respected district attorney. Ms. Bates never hesitated to investigate cases herself, often with the help of her sidekick, an investigative journalist named Larry. Don't let her having a male sidekick fool you, though. Ms. Bates was an attorney of action. She let her fists or her gun do the talking when called for, and needed the protection of no man. The men in Betty Bates' life followed her lead, not the other way around.