The University of Colorado tells women to use bodily fluids to hold off rapists

That's why you carry a gun too!

In seriousness though, obviously there are exceptions, but statistics show that much more often, it is men doing the shooting, not the other way around. In terms of MASS shootings, I don't know that there are any women on that list period.

Wife kills husband 22,000,000 results

For gods sake a wife ran over her husband for voting for Obama. Not to say women are worse/prone to doing such. This isn't meant to be sexist however, your suggestion comes with massive repercussions of people getting away with murder essentially.