he received those briefing materials before he, himself, went to meet with the president of ukraine, whereupon vice president pence told the ukrainians their aid would be held up until that investigation happened. that is not good for the vice president, right? that is exactly what the president is being impeached for. it really looks like he did it too, and worse, if he was the one who made it explicit. they wouldn't get their military aid if they didn't do it. well, the three chairs of the committee who are handling the bulk of the impeachment proceedings are confirming now that they are in this matter and this is the core issue of the impeachment. approaching a foreign government for dirt on a political rival for help on the next election in this country. and vice president pence appears to be made explicit the quid pro quo. they won't get their military aid unless they do it. so they announced they are investigating the president as part of the impeachment proceedings.