[cashflyer]

I don't know about individual state laws, but generally it is not illegal to own a bullet proof vest.

Though there are different levels of protection, the most common ballistic "bullet proof" vests do not stop most rifle rounds, nor some handgun rounds, and offer almost no protection against stabbing or pregnancy.

Harris and Klebold used shotguns and a 9mm carbine. A level 2 vest is required to stop the a 9mm round. And even the best vest can only protect the area that's covered. At least 3 of the Columbine victims were shot in the head.