ashley o parker, pulitzer prize winning reporter for "the washington post." and peter braaker, co-author of the new book "impeachment, an american history." barbara, i've got to start with you. how big, how consequential or not is tonight's court ruling? >> the ruling with regard to the mcgahn testimony, i think, is very significant. it doesn't reallys come as a surprise, but it's a very important step because what's i says isrt that witnesses cannot hide behind this c concept of absolute immunity. the judge says it doesn't exist, and these witnesses do have to testify, including don mcgahn. now, as a practical matter, the department of justice says it willde appeal this decision, so think they have the ability to sort of run out the clock on this opinion with regard to mpicgahn. but it could be used to empower other witnesses to testify in the impeachment proceeding. the house committee can wave it around. it may not be binding on any other witness, but it's certainly persuasive authority that suggests they do have to testify when thcalled. >> ashley parker, let's tal