Debevoise & Plimpton partner David O’Neil has been brought in to help U.S. Department of Homeland Security Secretary Alejandro Mayorkas ahead of any possible impeachment effort by the Republican-led House of Representatives, according to someone familiar with the hire. 

O’Neil is set to lead any needed defense along with Debevoise counsel Anna Moody and Carter Burwell, the source, who asked not to be named, told the National Law Journal Friday afternoon.