Harvard Law Professor Emeritus Alan Dershowitz said Wednesday that if President Trump's former lawyer Michael Cohen leaked the tape of his private conversation with Trump when that conversation was still subject to attorney-client privilege, he could be in trouble.

[Trump fumes: 'What type of lawyer would tape a client?']

"If it fact this material was originally leaked by Cohen when it was still privileged ... remember, a judicial officer found it to be privileged, it then was leaked only after it was leaked did [Rudy] Giuliani waive the privilege as to this in order to protect the privilege as to any other possible conversations ... if Cohen is the source of the leak, he has a serious problem," Dershowitz said on Fox News, indicating that Cohen may have violated attorney-client privilege.

"This was a conversation between a lawyer and a client that should never have been heard," he said.

CNN Tuesday night played a tape in which Trump and Cohen can be heard talking about some payment. CNN said the conversation is a reference to a payment to secure the rights to Playboy model Karen McDougal's story about her alleged affair with Trump.

Dershowitz said nothing on the tape would get Trump in any trouble, and said there's no hint of a crime.

"Not even a close question," he said. "There's no crime."

"Even if, and the tape is unclear, Trump raised the word 'cash,' it was then a discussion," Dershowitz said. "The lawyer said, 'no, no, no,' and President Trump said, 'no, we'll do it by check.'"

Dershowitz agreed, however, that the leak of the tape indicates that Cohen is "not as loyal to his client as he once was."