New York courts have not punished lawyers for sexual relationships that begin with former clients after the professional relationship has ended. Most states have adopted ethical rules making it a violation to have sex with clients.A slight majority of jurisdictions in the United States expressly ban attorney-client sexual relations that commence after the start of the representation. The American Bar Association's Model Rules of Professional Responsibility prohibit such affairs between a lawyer and his clients. Most lawyers seem to know that the 2 most famous ways of getting in ethical trouble involve commingling money and sleeping with clients. Bob Egelko, New California Rule Bans Lawyers from Having Sex with.