A law professor who served as the White House ethics lawyer under former President George W. Bush slammed Attorney General Jeff Sessions over reports that he lied to Congress about his communications with Russia.

According to the The Washington Post, Sessions spoke to the Russian ambassador twice last year and did not mention the conversations in his confirmation hearings.

If the report is true, it’s “a good way to go to jail,” said Richard Painter, who served as White House ethics lawyer between 2005 and 2007 and is now law professor for the University of Minnesota.

Misleading the Senate in sworn testimony about one own contacts with the Russians is a good way to go to jail https://t.co/qH0s6sTMJ9 — Richard W. Painter (@RWPUSA) March 2, 2017

I spent two hours with the Congressional Black Caucus today discussing Russian attacks on the US. Does AG Sessions have anything to say? — Richard W. Painter (@RWPUSA) March 2, 2017

Sessions on Wednesday denied he had any contact with Russia about the 2016 presidential campaign.

Earlier on Wednesday, The New York Times reported that White House officials under former President Barack Obama subtly tipped off intelligence agencies about their concerns about Trump’s ties to Russia.

Sessions is far from the only Trump official to be accused of improper contact with the Russian government. Former National Security Adviser Michael Flynn resigned last month following reports that he spoke to the Russian ambassador about sanctions before Trump took office. Other current and former Trump staffers accused of similar ethics violations include personal lawyer Michael Cohen, former campaign chief Paul Manafort and former adviser Roger Stone.