re: On another, completely trivial matter...
Assuming this actually gets dragged to the Supreme Court, the Court will probably point out patiently that "arrest" has an exact meaning, and that Jefferson is accused of a felony--you did note the word "felony" in the Constitution, right?--and please stop wasting their time.
I suspect the real reason the Congress has their panties in a bunch is because a lot of crooks have just been badly frightened.
Odd how two weeks ago it was all about the "culture of corruption," and now it's about standing in your Congressional office screaming "Sanctuary!"
More here.