By Luc Cohen and Jacqueline Thomsen (Reuters) – A U.S. congressional committee probing the Jan. 6, 2021, assault on the U.S. Capitol has sought to build a case that then-President Donald Trump behaved illegally when he tried to overturn his 2020 electoral defeat, but what charges could prosecutors bring against Trump and how might he defend himself? Here are some ideas being floated: OBSTRUCTING AN OFFICIAL PROCEEDING In a March 2 court filing, the committee detailed Trump’s efforts to persuade then-Vice President Mike Pence either to reject slates of electors for Joe Biden, who won the electi…