According to the University of Tallahassee, FL, between 800,000 and 2,500,000 crimes are stopped each year by guns. It is difficult to say what percentage of those would have been violent crimes that result in murder or serious injury, but there are on average 500 - 1000 accidential gun deaths each year. I think it is a far stretch to say a gun in the house is more likely to cause a death than prevent it. No one reports the crimes that didn't occur because someone defended themself. You only hear about the kid that blew away the neighbor, played roulette and lost or committed the mass shooting.