Republican U.S. Senate candidate Joe Arpaio, R-Ariz., says the federal Russia investigation should be scrapped in favor of an inquiry into the highly controversial claim that former President Barack Obama’s birth certificate is fraudulent.

After confirming that he still believes Obama’s birth certificate was forged, the Trump surrogate said that he has evidence from forensic experts backing his claim and therefore he won’t back down from it.

“I want to get it to Congress so they can pass some type of law,” the outspoken former sheriff explained on WABC Radio. “A regulation, that when somebody runs for president, you oughta check their background, so this won’t happen again. But I can’t get anybody, anybody to even look at it.”

Arpaio, who has been one of Trump’s biggest allies, told WABC that his experience in law enforcement is what has led him in 2011 to believe the former president forged his birth certificate.

“You know, you got that situation with [former national security adviser Michael] Flynn and all these guys in Washington they’re going after, because they didn’t check a box in a government report? OK, they didn’t check a box. Why don’t they check another government report? A forged document,” he argued, referencing the federal probe looking into Russian interference in the 2016 election.

“I’m not gonna back down on this. I don’t care if I lose elections or anything,” Arpaio said. “You gotta do what you feel is right, and not have these cover-ups and people not willing to look at everything we got. Why won’t they look at it? We sent it to the FBI two years ago. With a lot of other information. Where is it? They’re too busy talking about Russia.”

Arpaio made national headlines during his tenure as sheriff of Maricopa County in Arizona for his tough policing methods and stances on illegal immigration. Trump pardoned him after he was convicted of ignoring a federal court order in regards to a racial-profiling case.

The 85-year-old Republican revealed to the Washington Examiner this week that he will be running for Senate in Arizona, engaging in a tough race to fill the seat that is occupied by outgoing Sen. Jeff Flake, R-Ariz.

For years Trump pushed the “birther” movement against Obama, saying the former president was not born in Hawaii, as his birth certificate states. During the campaign he walked back that sentiment by holding a press conference to declare Obama was born in the U.S. However, an unnamed senator told the New York Times in November 2017 that Trump was still questioning whether his predecessor’s birth certificate is authentic.