Attorney Michael Cohen arrives to Trump Tower for meetings with President-elect Donald Trump on December 16, 2016 in New York.
BRYAN R. SMITH/AFP/Getty Imagess
Attorney Michael Cohen arrives to Trump Tower for meetings with President-elect Donald Trump on December 16, 2016 in New York.
Now playing
01:36
FBI raids Trump lawyer Michael Cohen's office
WASHINGTON D.C - SEPTEMBER 27: Judge Brett Kavanaugh testifies to the Senate Judiciary Committee during his Supreme Court confirmation hearing in the Dirksen Senate Office Building on Capitol Hill September 27, 2018 in Washington, DC. Kavanaugh was called back to testify about claims by Christine Blasey Ford, who has accused him of sexually assaulting her during a party in 1982 when they were high school students in suburban Maryland.  (Photo by Jim Bourg-Pool/Getty Images)
Pool/Getty Images
WASHINGTON D.C - SEPTEMBER 27: Judge Brett Kavanaugh testifies to the Senate Judiciary Committee during his Supreme Court confirmation hearing in the Dirksen Senate Office Building on Capitol Hill September 27, 2018 in Washington, DC. Kavanaugh was called back to testify about claims by Christine Blasey Ford, who has accused him of sexually assaulting her during a party in 1982 when they were high school students in suburban Maryland. (Photo by Jim Bourg-Pool/Getty Images)
Now playing
02:34
Was Kavanaugh picked to block Mueller probe?
Raskin & Raskin
Now playing
02:45
Trump lawyers quietly driving talks with Mueller
Rod Rosenstein, deputy attorney general, listens during a Senate Judiciary Committee confirmation hearing for Brett Kavanaugh, U.S. Supreme Court associate justice nominee for U.S. President Donald Trump, not pictured, in Washington, D.C., U.S., on Tuesday, Sept. 4, 2018. If confirmed, Kavanaugh would fortify the high court's conservative majority, and spotlight the rightward march of the federal judiciary under Trump and the GOP-controlled Senate. Photographer: Andrew Harrer/Bloomberg via Getty Images
Bloomberg/Bloomberg/Bloomberg via Getty Images
Rod Rosenstein, deputy attorney general, listens during a Senate Judiciary Committee confirmation hearing for Brett Kavanaugh, U.S. Supreme Court associate justice nominee for U.S. President Donald Trump, not pictured, in Washington, D.C., U.S., on Tuesday, Sept. 4, 2018. If confirmed, Kavanaugh would fortify the high court's conservative majority, and spotlight the rightward march of the federal judiciary under Trump and the GOP-controlled Senate. Photographer: Andrew Harrer/Bloomberg via Getty Images
Now playing
01:02
The man who oversees Mueller's investigation
Michael Cohen, President Donald Trumps personal lawyer walks down Park Avenue in New York June 15, 2018 after leaving his hotel. - President Donald Trump's personal attorney Michael Cohen has indicated that he is willing to cooperate with federal investigators to alleviate the pressure on himself and his family. (Photo by TIMOTHY A. CLARY / AFP)        (Photo credit should read TIMOTHY A. CLARY/AFP/Getty Images)
TIMOTHY A. CLARY/AFP/Getty Images
Michael Cohen, President Donald Trumps personal lawyer walks down Park Avenue in New York June 15, 2018 after leaving his hotel. - President Donald Trump's personal attorney Michael Cohen has indicated that he is willing to cooperate with federal investigators to alleviate the pressure on himself and his family. (Photo by TIMOTHY A. CLARY / AFP) (Photo credit should read TIMOTHY A. CLARY/AFP/Getty Images)
Now playing
02:06
ABC: Cohen has done interviews with Mueller
U.S. Deputy Attorney General Rod Rosenstein delivers remarks on "Justice Department Views on Corporate Accountability" during the The Annual Conference for Compliance and Risk Professionals at the Mayflower Hotel May 21, 2018 in Washington, DC. (Chip Somodevilla/Getty Images)
Chip Somodevilla/Getty Images
U.S. Deputy Attorney General Rod Rosenstein delivers remarks on "Justice Department Views on Corporate Accountability" during the The Annual Conference for Compliance and Risk Professionals at the Mayflower Hotel May 21, 2018 in Washington, DC. (Chip Somodevilla/Getty Images)
Now playing
05:41
Rosenstein: 12 Russians charged with hacking
CNN
Now playing
00:48
Trump: I believe Manafort will tell the truth at plea deal
Trump interview with NBC's Lester Holt. May 11 2017
NBC
Trump interview with NBC's Lester Holt. May 11 2017
Now playing
01:12
Sekulow: NBC edited Trump interview on Comey
CNN
Now playing
02:04
Starr: Mueller is getting closer to the truth
NBC
Now playing
01:30
Giuliani: Truth isn't truth
NEW YORK, NY - NOVEMBER 15: Don McGahn, general counsel for the Trump transition team, gets into an elevator in the lobby at Trump Tower, November 15, 2016 in New York City. President-elect Donald Trump is in the process of choosing his presidential cabinet as he transitions from a candidate to the president-elect. (Photo by Drew Angerer/Getty Images)
Drew Angerer/Getty Images North America/Getty Images
NEW YORK, NY - NOVEMBER 15: Don McGahn, general counsel for the Trump transition team, gets into an elevator in the lobby at Trump Tower, November 15, 2016 in New York City. President-elect Donald Trump is in the process of choosing his presidential cabinet as he transitions from a candidate to the president-elect. (Photo by Drew Angerer/Getty Images)
Now playing
03:27
Trump attacks NYT report in morning tweet
NEW YORK, NY - JUNE 9: Don McGahn, lawyer for Donald Trump and his campaign, leaves the Four Seasons Hotel after a meeting with Trump and Republican donors, June 9, 2016 in New York City.
Drew Angerer/Getty Images
NEW YORK, NY - JUNE 9: Don McGahn, lawyer for Donald Trump and his campaign, leaves the Four Seasons Hotel after a meeting with Trump and Republican donors, June 9, 2016 in New York City.
Now playing
02:27
NYT: WH counsel cooperating with Mueller probe
WASHINGTON, DC - JUNE 21:  Special counsel Robert Mueller (2nd L) leaves after a closed meeting with members of the Senate Judiciary Committee June 21, 2017 at the Capitol in Washington, DC. The committee meets with Mueller to discuss the firing of former FBI Director James Comey.  (Photo by Alex Wong/Getty Images)
Alex Wong/Getty Images
WASHINGTON, DC - JUNE 21: Special counsel Robert Mueller (2nd L) leaves after a closed meeting with members of the Senate Judiciary Committee June 21, 2017 at the Capitol in Washington, DC. The committee meets with Mueller to discuss the firing of former FBI Director James Comey. (Photo by Alex Wong/Getty Images)
Now playing
02:07
The Mueller investigation: Who could be next?
Now playing
02:20
Davis describes facing Mueller grand jury
CNN
Now playing
01:36
Analyst: Giuliani doing great harm to Trump
CNN
Now playing
02:00
Roger Stone: I'll never testify against Trump

Editor’s Note: Paul Callan is a CNN legal analyst, a former New York homicide prosecutor and current counsel at the New York law firm of Edelman & Edelman PC, focusing on wrongful conviction and civil rights cases. Follow him on Twitter @paulcallan. The opinions expressed in this commentary are his own.

(CNN) —  

The search warrant raid on the office, home and hotel room of Michael Cohen, the personal counsel to the President, is an extraordinarily unusual and highly aggressive move by federal prosecutors. It sends a strong message that Special Counsel Robert Mueller’s investigation has uncovered a lead suggesting criminality related to Cohen’s law office probably unrelated to Mueller’s Russia election meddling probe.

Mueller has now developed evidence sufficient to persuade a federal judge that there is “probable cause” to believe that Cohen has in his possession evidence of a crime. Most experienced criminal lawyers would likely suspect that the Stormy Daniels $130,000 “hush money” payoff is the primary clue that sparked a closer look at Cohen’s law office.

Everything about the payment looks unusual, from Cohen’s claim that he used a personal line of credit on his house to fund the payment to statements by both Cohen and the President that Mr. Trump knew nothing about the payment. Lawyers don’t customarily fund the contractual obligations of their clients as such actions can, depending on the circumstances, constitute unethical conduct by the attorney fronting or “gifting” the funds.

In addition, the timing of the $130,000 payment so close to the presidential election may suggest an unreported and illegal campaign contribution. How the money is treated for tax purposes may also trigger other legal concerns. Payments to people who claim to have had affairs with public figures are not currently tax deductible under the IRS Code even if your primary residences are Trump Tower and the White House.

The search warrants may uncover evidence of prior payoffs and the feds will have a strong interest in where the money came from and whether it was deducted as a Trump or Cohen business expense. Of course the search may also exonerate both men of any criminal conduct.

Cohen may have other problems. It is unethical for an attorney to act on behalf of a client without consulting the client. If Trump was not advised by Cohen that he had negotiated a $130,000 non-disclosure agreement with a porn actress prohibiting her from revealing anything suggesting an intimate relationship with Trump one month before the presidential election, he certainly should have been.

Cohen and the President have left room in their various accounts of the Daniels payment for Cohen to claim that as a long-time adviser, attorney and friend of the President he had been given general authority to act on behalf of Trump. That claim may get Cohen off the ethics hook but the whole Daniels “hush money” and Karen McDougal “catch and kill” deals look sleazy. It is hardly surprising that prosecutors would want to take a closer look.

If the crime were directly related to Mueller’s “Russia collusion” probe as the President is fond of describing his investigation, most of the heavy lifting regarding procurement and execution of the warrant would likely have been handled by Mueller’s office.

Instead initial reports suggest the search warrant was largely handled by the office of US Attorney for the Southern District of New York, Geoffrey Berman, a recent Trump appointee. Berman is also the former law partner of Rudolph Giuliani, one of Trump’s early supporters and advisers.

The fact that the search warrant was obtained and executed by the US Attorney for the Southern District rather than by the Office of Special Counsel Mueller clearly indicates that the special counsel was well aware that he was proceeding in a new direction that could subject him to criticism that he was exceeding his mandate.

It is also clear that if a prosecutor becomes aware of the commission of any crime, he has the lawful duty to follow the evidence. Mueller (or his supervisor Deputy Attorney General Rod Rosenstein) appears to have acted sensibly in referring the matter to the leading federal law enforcement official locally, the Manhattan based US Attorney, for proper follow-up.

This seizure of evidence pursuant to search warrant on an attorney’s office is a highly unusual and dangerous maneuver by any prosecutor. The attorney-client privilege protects most attorney records, and the courts, even when issuing a search warrant directed at an attorney’s office, require protection of legitimately “privileged” documents. Failure to protect such information can lead to court sanctions or even dismissal of a case.

The FBI and Justice Department use lawyers and investigators walled off from the primary investigation to sift through the documents to prepare a “privilege log” for later submission to the court. At least in theory these “taint” teams remove any legitimately privileged items from examination by the primary investigators putting the case together. Or at least that is how it is supposed to work, though some of us who are criminal defense lawyers may be skeptical.

There remains a very important exception to the attorney-client privilege called the “crime-fraud” exception. If the attorney and the client are conspiring to commit a crime and use the attorney-client privilege to cover up the conspiracy, under law the privilege is automatically waived.

New York federal prosecutors will be carefully sifting through Cohen’s records in search of any evidence that he conspired with his primary client, the President of the United States, to commit a crime. And the one thing we know for sure, a federal judge has reviewed the warrant application and has determined that there is “probable cause” to believe that Cohen’s law office records contain evidence of some kind of a serious crime: a crime so serious that this judge permitted a raid on the office of the President’s personal lawyer.

Get our free weekly newsletter

Something is up and President Trump’s latest musings about firing Mueller won’t make it go away. The new cop on this beat is Trump’s own appointee, US Attorney Berman, who like all federal prosecutors is ethically required to follow the evidence of a crime wherever it leads even if not in the direction of Russia…but instead into Trump Tower.