California is the most regulated state in America when it comes to restricting the sale, use, and ownership of guns. Gun-control advocates call it the national leader, the “tip of the spear” setting the tone for other states, as Christian Heyne of the gun-control advocacy group Brady puts it. The Golden State also has had a series of high-profile public mass shootings in recent years – most recently, in San Jose. On May 26, a gunman opened fire on co-workers at the Santa Clara Valley Transit Authority, killing nine people, then taking his own life. Why We Wrote This Under Ronald Reagan, California became the birthplace of the modern gun-control movement, and now has more than 100 laws. But how effective are they – and can they stop mass shootings like in San Jose?