Giuliani search warrant unconstitutional?

 Epoch Times:

The FBI’s recent raid on an apartment owned by Rudy Giuliani, a lawyer for former President Donald Trump, violated the Constitution, according to constitutional expert Alan Dershowitz.

“This was just a misuse of the search and seizure power. Initially, it was turned down; now it was approved, both by a judge and by the attorney general of the United States, so it wasn’t lawless action, but I believe that they acted inconsistently with both the spirit and the letter of the Constitution and that there should be remedies for it,” Dershowitz said on Newsmax on Saturday.

“It should be done through subpoena, and that is the constitutional route to getting evidence,” he added.

A search warrant being executed points to officials believing the subject would destroy evidence if the search was not carried out. But the lawyer knew that he was being investigated for months, so there’s no basis for a search unless a subpoena was obtained, Dershowitz argued.

“The 4th Amendment demands a subpoena in these situations, not a search warrant. What they did in this case was unconstitutional,” he said.

Agents obtaining information that is covered by attorney-client privilege would taint prosecutors who may try to prosecute Giuliani, Dershowitz added, saying that he has advised Giuliani’s lawyers on a pro-bono basis to move to get the material back, have the government subjected to subpoena analysis, and force anybody who goes over the material to be from outside the prosecutor’s office, such as a judge.
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I find this whole operation to be strange.  What is the alleged crime they are investigating?  Even if Giuliani possessed some "Russian disinformation" it is hardly a criminal offense.  Heck, the media publishes disinformation all the time such as the Russian collusion hoax.  While doing the search the agents apparently ignored evidence of alleged Biden corruption.  Why?