One police officer (and I imagine his sentiment is far from solitary) suggested it would be difficult to discern who the bad guy was, and who law-abiding citizens were, and you might end up with cops shooting anybody displaying a weapon who wasn't wearing a uniform.
It might be a good idea if police officers were trained not to shoot people who aren't wearing uniforms. Most people who aren't police officers don't wear uniforms, so if police officers get in the habit of shooting everyone who isn't wearing one there won't be anyone left to pay their salaries except U.S. Postal Service employees, FedEx and UPS drivers, and one guy in the Village People who probably is old enough to be collecting his retirement right now.
On the other hand if police officers are going to shoot anybody with a weapon who isn't wearing a uniform, there should be lots of continuing vacancies for plainclothes detectives and narcs. Then there shouldn't be an unemployment problem.
But then again if police officers must shoot anybody with a weapon who isn't wearing a uniform, it will be very dangerous to have a CWP and actually need to use it to defend your life. If the bad guy doesn't kill you the cops will. That's sort of not good, I think, and wasteful of the time and money it takes to get a Concealed Weapons Permit. It would be much more economical to just let the bad guy kill you. That way you could use the money you save to go out for a nice dinner and maybe buy some good sneakers, although they can be expensive.
On reflection, though, when disarmed people in colleges are attacked by a mass murderer today they have no option except to let the bad guy kill them or send a text message saying something like "Hey, there's a bad guy killing us all." If they were allowed the means to defend their lives, they might be able to prevent the bad guy from killing them and only have to worry about being killed by cops who are too bone stupid, incompetent, callous, and badly trained to not have worked out ways avoid killing the innocent people they should be protecting.
Perhaps the students who have Concealed Weapons Permits should wear cop uniforms, except that they might be embarrassed to dress like people who aren't smart enough to do their job. Maybe they could wear fake moustaches and big floppy shoes though.