Former New York City Police Commissioner Bernard Kerik, an ally of Donald Trump, is in discussions to be interviewed by federal prosecutors investigating the former president, according to Kerik's attorney.

Bernard Kerik served as New York's top cop in 2000 and 2001, under then-Mayor Rudy Giuliani. Two decades later, they worked together on an unsuccessful effort to find widespread voter fraud after Trump lost the 2020 presidential election.

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Kerik and Giuliani have defended the effort as legitimate and legal.

Earlier that year, Trump pardoned Kerik, who in 2010 was sentenced to four years in prison after pleading guilty to eight felony charges for offenses, including failure to pay taxes and lying to White House officials.

Kerik's attorney, former Trump lawyer Tim Parlatore, told CBS News Thursday that he expects the interview to happen "soon." 

Giuliani has previously met with investigators for special counsel Jack Smith in connection with the Justice Department's investigation into alleged efforts to interfere with the peaceful transfer of power after the 2020 election.

Kerik's potential meeting with Smith's team comes as Trump himself indicated Tuesday he may be indicted in the probe. Trump revealed that he received a letter from the Justice Department identifying him as a target in the criminal investigation.

The target letter highlights three federal statutes, according to a senior Trump source. Potential charges under those statutes include conspiracy to commit an offense or to defraud the U.S.; deprivation of rights under color of law; and obstruction of an official proceeding.

The investigation has cast a wide net, with interviews and grand jury appearances by current and former officials from Georgia and Arizona, as well as Trump's closest confidants, who engaged in strategy sessions at the White House in 2020 and 2021.

Trump said Tuesday he was given the opportunity to testify before a federal grand jury. He repeated his claim that the special counsel is engaged in a "witch hunt" and criticized the investigation as a "complete and total political weaponization of law enforcement."

Graham Kates is an investigative reporter covering criminal justice, privacy issues and information security for CBS News Digital. Contact Graham at [email protected] or [email protected]