Harvard Law professor emeritus Alan Dershowitz, who once represented disgraced financier Jeffrey Epstein, says his former client’s longtime co-conspirator, Ghislaine Maxwell, “knows everything” about the Epstein case and should be offered immunity to testify before Congress.

Ex-socialite Ghislaine Maxwell will try to cut a deal with federal authorities during a jailhouse meeting with Deputy Attorney General Todd Blanche, sources told The Post.