It took them how long to come up with this theory?

How long have we been saying this? With this type of delayed deductive reasoning, how did we ever "evolve" from the apes???

"The other statistic that emerged from a study of active killers is that they almost exclusively seek out "gun free" zones for their attacks.
In most states, concealed handguns are prohibited at schools and on college campuses even for those with permits.
Many malls and workplaces also place signs at their entrances prohibiting firearms on the premises.
Now tacticians believe the signs themselves may be an invitation to the active killers. The psychological profile of a mass murderer indicates he is looking to inflict the most casualties as quickly as possible.
Also, the data show most active killers have no intention of surviving the event."

I've been trying to impress on my daughter that it's simply not safe to enter businesses with "no guns allowed" signs posted. The reasoning is this: the only people in the business with a gun would be a criminal. Since law abiding citizens follow the rules, they'll leave their concealed carry guns in their cars. This leaves the only people with guns in the business; criminals. Hence, it's not safe to enter establishments with these signs posted.