Cohen is an amazing scumbag. He is the President’s lawyer who has a professional duty to maintain the confidentiality of his client and he turns into a Judas Iscariot.
He went to law school and passed the bar exam to get a license to practice law, but I believe Trump was his only client.
You find mutants like this all over the NYC business world. They aren't really lawyers. Their job is to conduct questionable business deals on behalf of their one "client" while protecting the client from legal scrutiny.