So, I’m a little confused. I’m applying for citizenship, and as part of that process I will have to answer 10 questions that may include ones about the US system of government. I have duly studied, and to the question “what is the function of the Supreme Court”, one of the accepted answers is “to determine whether or not an action is constitutional”.

We are in the process of impeaching the last president, and this constitutionality question has come up: can you impeach a President who is no longer in office? However, it appears that this question was not decided by the Supreme Court, but by a simple vote in the Senate.

I’m confused. Is the Senate not itself conforming to the Constitution in this case? What am I supposed to tell he examiner?