As a self-described libertarian -

I respect the job the police do, and I wouldn't want to have to do it myself. But that is completely orthogonal to holding individual police officers accountable under the same laws as everybody else. Agents of the state summarily executing people is one of the most egregious violations of individual liberty possible - larger than "licensing for lawn cutting" or most anything else. The "thin blue line" flag is a counter protest to the call for police accountability, and it is blatantly hypocritical to call yourself a libertarian while opposing a major libertarian critique.

Libertarians should want Taft-Hartley and other wage-suppressing regulations abolished first. They don't because free markets are really just code for making sure owners win and workers lose.