Legal experts were stunned at news that President Donald Trump's former longtime lawyer Michael Cohen secretly recorded his old boss.

The conversation apparently centered on payments made to former Playboy model Karen McDougal, who has alleged an affair with Trump.

Cohen is under investigation in the Southern District of New York, and his involvement in payments to McDougal and other women is under scrutiny from prosecutors.

Legal experts were stunned at news that President Donald Trump's former longtime lawyer Michael Cohen secretly recorded his old boss having a conversation about payments made to a former Playboy model who claimed she had an affair with Trump.

And the sheer existence of that tape, some said, was bad news no matter what was said on it.

"It's never a good thing when you're talking to a suspected criminal about matters under which he's under investigation," Renato Mariotti, a former federal prosecutor who's now a partner at Thompson Coburn, told Business Insider. "And it's even worse when you're being recorded."

On Friday, The New York Times reported that Cohen recorded a conversation with Trump just two months ahead of the 2016 election in which they discussed payments to former Playboy model Karen McDougal. That recording was among several the FBI seized in April when it raided Cohen's properties. Meanwhile, the tape seemed to contradict the Trump campaign's past denial of any knowledge of such payments to McDougal.

Cohen is the focus of a criminal investigation in the Southern District of New York into whether he violated campaign-finance laws, committed bank fraud or wire fraud, engaged in illegal lobbying, or participated in other crimes. The FBI seized more than 4 million documents in those April raids.

The National Enquirer purchased McDougal's story of an affair with Trump for $150,000 in August 2016. But the outlet never published the piece. That practice is known as "catch and kill," and it effectively silenced McDougal's allegations. Federal investigators had sought documents in the Cohen raids related to that payment and similar payments to other women.

David Pecker, the head of American Media Inc., which publishes the National Enquirer, is a longtime friend of both Trump and Cohen. Citing a person familiar with the recording, The Washington Post reported Friday that in it, Cohen and Trump discussed a plan to purchase the rights to McDougal's story from Pecker's company for about $150,000.

'It's hard to spin taped conversations between the president and Cohen being good for the president'

Trump's attorney Rudy Giuliani confirmed to The Times that Trump discussed payments to McDougal with Cohen, but he said that ultimately no payment was made. Giuliani said the recording was less than two minutes long, and that there was no indication based on it that Trump knew of the payment to American Media Inc. beforehand.

"Nothing in that conversation suggests that he had any knowledge of it in advance," Giuliani told the newspaper of the payment to American Media Inc. Giuliani added that Trump told Cohen that if he did pay McDougal, it should be in the form of a check instead of cash so that it could be properly recorded, The Times said.

"In the big scheme of things, it's powerful exculpatory evidence," Giuliani said.

Trump. Win McNamee/Getty Images But another source told CNN that the conversation was not as Giuliani described, saying the tape was in no way good for Trump. Citing a source familiar with the tapes, CNN reported that Trump, when informed about the September 2016 tape, said, "I can't believe Michael would do this to me."

Giuliani and Peter Stris, McDougal's lawyer, did not respond to request for comment from Business Insider. Lanny Davis, one of Cohen's attorneys, declined to comment. In a Friday evening tweet, Davis said the recording "will not hurt" Cohen once it is heard, and that "any attempt at spin can not change what is on the tape."

Experts agreed.

"It's hard to spin taped conversations between the president and Cohen being good for the president," Mariotti told Business Insider in response to Giuliani's comments. "It strikes me as really bad, and the question is just how bad it is."

Mariotti said the recordings could shed light on Trump's knowledge of any false statements made by Cohen, particularly to financial institutions, or on whether Trump himself made any false statements regarding the payments that could run afoul of campaign finance laws.

Ken White, a criminal-defense attorney, told Business Insider that the tape "could move Trump closer to danger."

"Suddenly we're not talking about whether Cohen flips and whether his testimony should be believed," White said. "Suddenly we have recorded words from Trump's own mouth about his knowledge of and participation in the hush money payments. If the discussion includes anything about doing the payments, or recording the payments, in a way that defrauds a bank or violates campaign finance law, we're off to the races."

Experts were shocked that Cohen felt the need to record a conversation with Trump

The fact that Cohen felt the need to record a conversation with Trump struck multiple experts as bizarre. Some said they had never heard of an attorney recording secretly recording a client.

The New York State Bar Association calls such secret recording unethical. New York, where the taping reportedly took place, legally requires only one person's consent for such a recording. So Cohen's actions were not illegal.

"It's very bizarre and at the very least, creates ethical questions for Cohen," Mariotti said. "Lawyers have a duty of confidentiality for their clients. Now, the conversations between Trump and Cohen may not be privileged, but by creating a tape record you are potentially putting the confidentiality of your client's communications at risk. Most lawyers take great care at protecting the confidentiality of their clients information."

He added that the rationale behind doing so was a mystery. Perhaps, he said, Cohen "thought it would give him some leverage over Trump."

"Why he thought he needed that leverage, I don't know," Mariotti said.

Harvard University law professor Alan Dershowitz, who has proven to be somewhat of an ally to Trump as he combats special counsel Robert Mueller's probe into Russian election interference, told Business Insider that there are big questions that remain regarding the tape.

Among them: Who leaked it, what was said on it, is it even permissible for an attorney to secretly record his client, is there anything incriminating on it, and are there other recordings of discussions between Cohen and Trump?

Dershowitz said he had never heard of an attorney recording his client in this manner.

He added that if Cohen or anyone associated with him was involved in the leak of the tape, it could hurt his ability to reach a deal with prosecutors, if that's what he wishes.

It "would make him a less trustworthy potential witness," Dershowitz said.

Mitchell Epner, an attorney at Rottenberg Lipman Rich who was previously an assistant US attorney for the District of New Jersey, told Business Insider that Cohen could have made the recording either "for his own protection" or to ensure he got repaid for an expenditure he thought could have been agreed to in the conversation.

"I can tell you that in all of the time that I have practiced law, and all of the time that I have talked to other people who've practiced law, I have never encountered an attorney in good faith recording a conversation with a client, other than as self-protection when you think something very inappropriate may be going on," Epner said. "Either something wasn't kosher or he was afraid that he was going to be out a bunch of money."