“Secretary Mayorkas has brazenly refused to enforce the laws passed by Congress and has enacted policies that knowingly make our country less safe,” Green said. “What we’re seeing here is a willful violation of the oath of office taken by Secretary Mayorkas. Let me repeat that, ‘a willful violation.'”

He went on to say that “gross incompetence,” which he accused Mayorkas of — citing 8.1 million encounters at U.S. borders, including 6.7 million at the U.S.-Mexico border — was sufficient grounds for impeachment, arguing he did not have to be found guilty of criminal behavior.

“Secretary Mayorkas’ refusal to follow the law is sufficient grounds for impeachment proceedings. The constitutional history is overwhelmingly clear on this-the Founders designed impeachment not just to remove officials engaged in criminal behavior, but those guilty of such gross incompetence that their conduct had endangered their fellow Americans, betrayed the public trust, or represented a neglect of duty,” Green said in his opening statement.

Ranking Democrat Rep Bennie Thompson, D-Miss., fired back in his own opening statement, calling the effort to oust Mayorkas a sham impeachment.

“Despite what Republicans would have Americans believe, Secretary Mayorkas is enforcing immigration law,” Thompson said during his opening remarks at Wednesday’s hearing.

Thompson declared that the facts show Mayorkas is doing his job on border security and immigration enforcement and alleged Republicans are targeting Mayorkas because they think it will benefit them politically.

“You cannot impeach a cabinet Secretary because you do not like a president’s policy,” Thompson said. “That’s not what impeachment’s for. That’s not what the constitution says.”

The House last week agreed to hold the impeachment proceedings against Mayorkas with Green alleging he was guilty of dereliction of duty, citing interviews with eight U.S. border patrol agents which he said revealed “Mayorkas’ failure to enforce the laws of the United States and instead implementing policies that have caused and perpetuated this immigration crisis.”

DHS spokesperson Mia Ehrenberg said then that there was “no valid basis” to impeach Mayorkas, who at the time told MSNBC he would cooperate with the proceedings.

Wednesday’s hearing featured testimony from Republican attorneys general from Montana, Oklahoma and Missouri.

Montana Attorney General Austin Knudsen testified that while the situation at the U.S.-Mexico border “presents a difficult challenge for any administration” he believed that Mayorkas and the broader Biden administration “have absolutely poured gasoline on this fire.”

Frank Bowman, a professor emeritus of law at the University of Missouri School of Law who was invited to testify by Democrat, however testified that “nothing” he had seen in arguments about Mayorkas’ policy decisions “rises to the level of an impeachable offense.”

“If members of this committee disapprove of the Biden administration’s immigration and border policies, the Constitution gives this Congress a wealth of legislative powers to change them — impeachment is not one of those powers,” Bowman said.

At the conclusion of the hearings, the Homeland Security Committee will hold a markup on impeachment articles against Mayorkas, then hold a vote on them before sending them to the full House to consider.