What to know about the key laws invoked in the scores of Trump legal challenges

Washington — Dozens of lawsuits have been filed in the past month challenging executive actions President Trump has taken since the start of his second term in office, and federal courts from coast to coast have started scrutinizing the president's plans.

The challenges are aimed at unwinding many of the president's policies, which they believe are unlawful. They have targeted his plans to crack down on illegal immigration, shrink the size of the federal government and cut spending, as well as Mr. Trump's pledge to end what he believes is the weaponization of the Justice Department and FBI.

Many of the lawsuits hinge on alleged violations of decades-old federal laws: The Administrative Procedure Act, the Privacy Act and the Impoundment Control Act. The measures prescribe certain procedures and policies that the executive branch must follow when it comes to taking certain actions.