So, I did ask some pointed questions of an excellent AUSA earlier this week. I will ask one more, who also posts on these boards when I get a chance.
Suffice it to say, his answer really shocked me, and I will not post it here. Sanitized version is: Not only did he not see muzzling as a crime in any way, but he thinks that "we" have a lot more leeway in using lethal force than I think we do. So, he is now my on call lawyer:-)
You have to remember though, that he is really only concerned about what the 4th Amendment says, not some elected or appointed official who can't read a dictionary.