While Congress retains its inherent contempt authority and may exercise it at any time, this inherent contempt process was last used by the Senate in 1934, in a Senate investigation of airlines and the U.S. Postmaster.
To make a scared cat feel more comfortable, set up a covered cave for them to retreat to. Line it with soft bedding and partially cover the entrance so that the cat will feel safely obscured inside. In the same vein of thought, you can purchase a cat tower for the cat to lie on top of.
Just like people, there are all manner of reasons that your kitty could be nervous. Many nervous cats have experienced some kind of trauma like abuse or a dog attack. Others are just not socialized, so they aren't used to being around people and living in a home, especially if they were alley cats. They may be afraid of dogs, other cats, or even strange things like trash cans.