Representative Mark Green, Chairman of the House Homeland Security Committee, is spearheading an investigation into Homeland Security Secretary Alejandro Mayorkas, alleging a "dereliction of duty" in his handling of the border crisis. Green held a press conference on Wednesday outlining the accusations and convened a hearing featuring testimony from border security experts, including former acting DHS Secretary Chad Wolf and former Border Patrol Chief Rodney Scott. Joe Edlow, the former acting director of U.S. Citizenship and Immigration Services, also provided testimony.

Green contends that Mayorkas has disregarded his constitutional oath and undermined border security by rescinding 89 policies from prior administrations. This action, Green argues, led to a surge in illegal immigration as migrants exploited the perceived vulnerabilities of the system. He emphasized that Mayorkas's "catch and release" policies have exacerbated the situation, resulting in millions of border crossings.

The investigation comes amid calls from some Republicans for Mayorkas's impeachment, although Green has clarified that impeachment is not the immediate objective of the committee's inquiry. Green asserts that Mayorkas has violated or undermined at least ten laws and ignored multiple court orders. He criticizes Mayorkas for disregarding the constitutional principle of the legislative branch creating laws and the executive branch enforcing them.

Illegal immigration has significantly increased under the Biden administration, with Customs and Border Protection (CBP) reporting a substantial rise in monthly encounters since Biden took office. CBP figures show a jump from around 100,000 monthly encounters in Biden's first full month to over 200,000 currently, with numbers even exceeding 230,000 in late 2022 and early 2023. This surge has prompted some Republicans to introduce articles of impeachment against both Biden and Mayorkas, although these efforts have been largely symbolic. Public opinion polls consistently show Biden's handling of the border crisis as one of his weakest areas of approval.