I believe this is the most important issue in this whole story. Checkpoints are unconstitutional -- a direct violation of the 4th Amendment.
I have never seen a checkpoint in my state (we believe in the Bill of Rights out here in the Rockies), but I have seen them in the South. There, though, not too many checkpoints get set up around the upper class neighborhoods, ya know? They're set up to catch poor people for victimless crimes, justify the existence of twice as many cops as a town needs, and to generate revenue.
Now then... there are plenty of folks who are going to say "well, I'm not doing anything wrong, all my papers are in order, I'm a Party member..." Looks like it's pretty easy for your papers to not be in order. Or maybe someone gets it in for you, and clicks a button on a Motor Vehicle department computer. One click of a button, your life is a wreck.
Is this the kind of country any of you want to live in?