A Donald Trump ally has turned over thousands of documents to special counsel Jack Smith related to efforts to find supposed voter fraud in the 2020 presidential election -- including materials that haven't been previously disclosed to investigators looking into events surrounding January 6, 2021.

Former New York Police Commissioner Bernie Kerik was part of the team led by Trump attorney Rudy Giuliani trying to uncover fraud that would swing the election in favor of Trump.

For months, Kerik had tried to shield some of the documents from investigators, citing privilege.

But in recent weeks, Kerik gave the documents to the Trump's 2024 campaign to review. After that review, the campaign declined to assert privilege, according to Kerik's lawyer, Tim Parlatore, who turned over the documents to Smith's office on Sunday.

"I have shared all of these documents, approximately 600MB, mostly pdfs, with the Special Counsel and look forward to sitting down with them in about 2 weeks to discuss." Parlatore said.

Kerik is scheduled to sit down for an interview with the special counsel's office next month, CNN has learned.

Among the materials now in Smith's possession are witness statements, research and other documents produced by Giuliani's team.

When the January 6 congressional committee subpoenaed Kerik for documents, he provided a log of his communications that he said he was withholding due to privilege. Those communications have never been disclosed publicly, as the committee did not challenge Kerik's privilege claims in court.