They're assuming the role of the Executive branch. They have no authority over whether or not the President declassifies anything. Funny how they shrug off Congress ordering the same agencies ignore an order from the Senate to produce documents the Senate wants to see but now expect obedience.
Scum bucket Schumer told Trump the Intelligence agencies had six ways from Sunday to screw him. It looks like he knew because he was in on their activities which is exactly why he doesn't want things declassified. Full declassification will show that some people in Congress were kept informed of how the coup plotting was coming along. Schumer probably among them.
JMHo
I'm on my knees