This cop is well spoken for a black guy. And he nails it on the head when he points out that these protesters are obviously agents provocateur who are there to disrupt the pro Trump rally.
Trying to prevent people from freedom of assembly is a violation of the Constitution, specifically the First Amendment. But, the U.S. Constitution has no force or effect unless you actively claim your rights. ;)
"When bad men combine, the good must associate; else they will fall, one by one." Edmund Burke