One of the things that concerns me about some of the suggestions here is the idea of being able to reliably ID LEO once they break down your door without warning.
I'm sure most people are far more tactically fit than I am, but as an average Joe nobody, even with 12 years military xp, I wouldn't know a cop from Ronald McDonald if he kicked my door down in the middle of the night while I was sitting on the couch picking my nose. For me, that door goes down and I don't care if it's the Publishers Clearing House Prize Patrol, I'm opening fire.
Also, and I know this will piss the LEO members off to no end, but if anyone (and yes I do mean anyone) so much as pointed a gun at one of my dogs, I would see it as the same thing as if they pointed it at one of my kids (yes I have kids, so I know the difference). My dogs are family; they sleep inside, I feed them the best I can afford, and I never hesitate to treat them at the vet. If someone, even a cop, shot one, they'd have to shoot me next because it would take the entire swat team to pull me off them.
Fortunatly, I live in a rural area where mistaken residences are unheard of. Houses here are known as "The X-family Ranch", so if we had a rash of no-knocks, it would be criminals doing criminal things. Still, I question a person's ability, after a hard day, dealing with all the domestic stuff, relaxing on the lazyboy, reliably IDing a legit LEO smashing through the front door with the wife/kids screaming and the dog(s) howling, fumbling with your gun, etc.
"Well, it's rather brutal here. Right now we are advising all our clients to put everything they've got into canned food and shotguns."