Now, why a background check on the private sale of firearms would not have had a effect on the Columbine shooting. Both of the shooters were 17 years old at the time. They were already prohibited from purchasing a firearm. The two men that sold firearms to the 17 year olds, knew that they were under age, but sold them a firearm anyway, so even if there was a requirement for a background check, clearly the sellers and buyers in this case would not have followed the law. In addition, the shooters built 99 improvised explosive devices, which is already against the law, a law that they did not adhere to.
What's your thoughts?