Rep. Jamie Raskin (D-Md.) highlighted House Republicans’ head-scratching criteria for impeachment proceedings when it comes to Donald Trump vs. Joe Biden.

“What’s amazing to me is that you’ve got an overwhelming number of people in their caucus who voted against impeaching Donald Trump for inciting a violent insurrection against our own House, against the Congress, against the vice president,” Raskin told MSNBC’s Jen Psaki on Thursday.

He added, “Now, they want to go ahead and launch an impeachment inquiry against Joe Biden for a crime unknown. No one can identify what the alleged offense is.”

The House Republican caucus voted unanimously on Wednesday to formally open an impeachment inquiry into Biden, pushing ahead in its yearlong investigation of his family that has yet to produce evidence of wrongdoing by the president.

Democrats have accused Republicans of weaponizing impeachment for political revenge at Trump’s bidding. Republicans claim formalizing the inquiry will give them more authority to enforce subpoenas to continue the investigation.

In 2021, 10 House Republicans joined Democrats in voting to impeach Trump for a second time over his role in the Jan. 6, 2021, attack on the U.S. Capitol.

Trump’s supporters laid siege to the Capitol, assaulting law enforcement, damaging government property and threatening to kill Vice President Mike Pence, after the then-president spent months telling them lies that the 2020 election had been rigged.

Trump was impeached on one charge, incitement of insurrection. Raskin was one of the lawmakers who drafted the resolution.

Trump was ultimately acquitted by the narrowly divided Senate, which required a two-thirds vote to convict.