Representative Mark Green, the chairman of the Homeland Security Committee, announced he would retire from Congress, adding to the number of powerful G.O.P. chairmen who will not return.
The first House hearing on impeaching the homeland security secretary featured Republicans accusing him of willfully failing to enforce immigration laws and an expert who testified there was no case.
Not enough Republican members are yet on board with either impeachment proceedings against the Homeland Security secretary or border security legislation.
House Republicans are preparing a cascade of investigations, some overlapping, into the Biden administration and its policies. Right-wing lawmakers have said the ultimate goal is to impeach the president.