TLDR: Death from mass shootings are very rare (on par with lightning strikes). Efforts to reduce them may cause more deaths than they prevent by wasting money that would've been better spent on more tractable causes of death.
Many of responses I've seen to the recent mass shooting by Elliott Rodgers have been calls for more gun control.
However, in terms of relative risk, the danger mass shootings pose is miniscule. A 2013 Congressional Research Service Report "....defines "public mass shootings" as incidents involving four or more deaths and "gunmen who select victims somewhat indiscriminately," excluding drug trafficking, gang activity and terrorism.
By that measure, there have been 78 such incidents in the U.S. since 1983, claiming a total of 547 lives. Horrifying as that toll is, it represents a substantially lower risk than lightning strikes, which have killed 54 Americans a year on average over the last 30 years..."
http://www.washingtonexaminer.com/gene-healy-no-guarantee-more-gun-laws-will-prevent-next-newtown-tragedy/article/2527210
Gun crime overall is down by half since the 1990's, despite (because of?) the relaxation of concealed carry laws in many states, and the expiration of the Assault Weapons ban.
Unfortunately, like terrorist attacks, mass shootings are highly salient--they get large amounts of coverage from the news, and arouse strong emotions. Therefore, as with terrorist attacks, there is a strong temptation to badly overreact, and implement policies that are futile and wasteful, at best, or actively harmful at worst.
For example, the TSA costs $64 million to $600 million/life saved:
"What Stewart and Meuller found is staggering: they estimate that the DHS, of which the TSA is a part, spends between $64 million and $600 million to save just one life from domestic terrorism--60 times the $1 million to $10 million per-life goal set by the U.S. Office of Management and Budget"
Another study found that due to the hassle of TSA screening procedures more people were driving instead of flying. Since driving is more dangerous than flying, that means that TSA's regulations resulted in death equivalent to "four fully loaded Boeing 737s crashing each year"
http://fivethirtyeight.blogs.nytimes.com/2010/11/18/the-hidden-costs-of-extra-airport-security/?pagewanted=all
New gun control legislation would likely be an equally poor way to spend money/life saved. We already have laws on the books that require background checks designed to prevent criminals and the insane from getting guns. Rodgers underwent background checks when he legally purchased his guns. He had no criminal record, and had not been involuntarily committed (the criteria that would've flagged his purchases). The police even visited him, based on concern expressed by his family. He was able to persuade them that he was not a threat to himself or others.
So, is nothing to be done? While I think additional regulation to address mass shootings specifically is likely to be harmful, there's much that we could do that is desirable for other reasons, which may also help reduce mass shootings.
1. Increase the number of concealed carry permit holders by requiring cities to issue permits on a "shall issue" basis. Many cities make it difficult/impossible for anyone other than police or the politically connected to get a concealed carry permit. By making it easier for law-abiding citizens to carry arms, you increase the probability that someone will be able to stop a mass shooter before the police arrive.
2. Reduce the number of "gun free" zones. Many parts of the US are "gun free" zones, which prevent law-abiding people from carrying guns (such as the UCSB campus). Therefore, law abiding people are disarmed, while criminals are armed. A criminal can reasonably expect to kill a large number of people before the police arrive. If more people were armed, then they could prevent the shooter early in the rampage. Since mass shooters are driven by the desire to "show them" and go out in a famous blaze of glory, it reduces their incentive to do so if they're likely to be taken out by an armed citizen early in their rampage.
3. Increase the number of non-profits devoted to "at risk" individuals (i.e. kids expressing violent intent, kids harming animals, etc.) Try to get them tracked into classes in how to talk to girls, how to make friends, how to control anger, how to recognize irrational thoughts, etc.
4. Teach proper life skills in high school (money management, how to start a business, buying insurance, get and keep a job, how to avoid procrastination). Many mental illnesses flare up due to stress, which in turn, is often caused by poor life skills.
5. Eliminate medical licensure and the FDA. By driving down the barriers to entry to the medical field, and the cost of new drugs, people with mental illness would be better able to afford treatment, and we might have better treatments to give them.
6. Eliminate zoning regulations and building codes. A significant cause of stress is the cost of housing in many parts of the US. The more their basic needs can be met without stress, the less likely the mentally ill are to lash out violently.
7. Legalize MDMA. Many mass shooters are lonely, depressed, and friendless. They don't know how to connect to people, how to empathize with others, or what it feels like to be happy. And all they see ahead of them is a life of loneliness and pain. MDMA can help someone feel happy and connected, even if it is only while they are on the drug. That, in turn, could give them hope that their life can be different.
8. Legalize LSD/psylocibin. Again, many shooters feel disconnected from humanity, fail to feel empathy for others, and that life is pointless. Many of them are extremely self-centered and narcissistic. LSD/psylocibin can change that.
9. Legalize prostitution. Many shooters are sexually frustrated males. Due to personality defects, they find it extremely difficult to attract affection from any woman. While purchasing the services of a prostitute isn't a perfect solution, it can help them feel less frustrated and angry until they can figure out how to relate better to women.
However, even if we did all of the above, there would still be mass shootings. In a country of 310+ million people, there will always be a small percentage of people whose mental illness drives them to commit murder. At a certain point, devoting resources to stop them becomes counterproductive, and it would be better to devote those resources to more tractable problems.
Many of responses I've seen to the recent mass shooting by Elliott Rodgers have been calls for more gun control.
However, in terms of relative risk, the danger mass shootings pose is miniscule. A 2013 Congressional Research Service Report "....defines "public mass shootings" as incidents involving four or more deaths and "gunmen who select victims somewhat indiscriminately," excluding drug trafficking, gang activity and terrorism.
By that measure, there have been 78 such incidents in the U.S. since 1983, claiming a total of 547 lives. Horrifying as that toll is, it represents a substantially lower risk than lightning strikes, which have killed 54 Americans a year on average over the last 30 years..."
http://www.washingtonexaminer.com/gene-healy-no-guarantee-more-gun-laws-will-prevent-next-newtown-tragedy/article/2527210
Gun crime overall is down by half since the 1990's, despite (because of?) the relaxation of concealed carry laws in many states, and the expiration of the Assault Weapons ban.
Unfortunately, like terrorist attacks, mass shootings are highly salient--they get large amounts of coverage from the news, and arouse strong emotions. Therefore, as with terrorist attacks, there is a strong temptation to badly overreact, and implement policies that are futile and wasteful, at best, or actively harmful at worst.
For example, the TSA costs $64 million to $600 million/life saved:
"What Stewart and Meuller found is staggering: they estimate that the DHS, of which the TSA is a part, spends between $64 million and $600 million to save just one life from domestic terrorism--60 times the $1 million to $10 million per-life goal set by the U.S. Office of Management and Budget"
Another study found that due to the hassle of TSA screening procedures more people were driving instead of flying. Since driving is more dangerous than flying, that means that TSA's regulations resulted in death equivalent to "four fully loaded Boeing 737s crashing each year"
http://fivethirtyeight.blogs.nytimes.com/2010/11/18/the-hidden-costs-of-extra-airport-security/?pagewanted=all
New gun control legislation would likely be an equally poor way to spend money/life saved. We already have laws on the books that require background checks designed to prevent criminals and the insane from getting guns. Rodgers underwent background checks when he legally purchased his guns. He had no criminal record, and had not been involuntarily committed (the criteria that would've flagged his purchases). The police even visited him, based on concern expressed by his family. He was able to persuade them that he was not a threat to himself or others.
So, is nothing to be done? While I think additional regulation to address mass shootings specifically is likely to be harmful, there's much that we could do that is desirable for other reasons, which may also help reduce mass shootings.
1. Increase the number of concealed carry permit holders by requiring cities to issue permits on a "shall issue" basis. Many cities make it difficult/impossible for anyone other than police or the politically connected to get a concealed carry permit. By making it easier for law-abiding citizens to carry arms, you increase the probability that someone will be able to stop a mass shooter before the police arrive.
2. Reduce the number of "gun free" zones. Many parts of the US are "gun free" zones, which prevent law-abiding people from carrying guns (such as the UCSB campus). Therefore, law abiding people are disarmed, while criminals are armed. A criminal can reasonably expect to kill a large number of people before the police arrive. If more people were armed, then they could prevent the shooter early in the rampage. Since mass shooters are driven by the desire to "show them" and go out in a famous blaze of glory, it reduces their incentive to do so if they're likely to be taken out by an armed citizen early in their rampage.
3. Increase the number of non-profits devoted to "at risk" individuals (i.e. kids expressing violent intent, kids harming animals, etc.) Try to get them tracked into classes in how to talk to girls, how to make friends, how to control anger, how to recognize irrational thoughts, etc.
4. Teach proper life skills in high school (money management, how to start a business, buying insurance, get and keep a job, how to avoid procrastination). Many mental illnesses flare up due to stress, which in turn, is often caused by poor life skills.
5. Eliminate medical licensure and the FDA. By driving down the barriers to entry to the medical field, and the cost of new drugs, people with mental illness would be better able to afford treatment, and we might have better treatments to give them.
6. Eliminate zoning regulations and building codes. A significant cause of stress is the cost of housing in many parts of the US. The more their basic needs can be met without stress, the less likely the mentally ill are to lash out violently.
7. Legalize MDMA. Many mass shooters are lonely, depressed, and friendless. They don't know how to connect to people, how to empathize with others, or what it feels like to be happy. And all they see ahead of them is a life of loneliness and pain. MDMA can help someone feel happy and connected, even if it is only while they are on the drug. That, in turn, could give them hope that their life can be different.
8. Legalize LSD/psylocibin. Again, many shooters feel disconnected from humanity, fail to feel empathy for others, and that life is pointless. Many of them are extremely self-centered and narcissistic. LSD/psylocibin can change that.
9. Legalize prostitution. Many shooters are sexually frustrated males. Due to personality defects, they find it extremely difficult to attract affection from any woman. While purchasing the services of a prostitute isn't a perfect solution, it can help them feel less frustrated and angry until they can figure out how to relate better to women.
However, even if we did all of the above, there would still be mass shootings. In a country of 310+ million people, there will always be a small percentage of people whose mental illness drives them to commit murder. At a certain point, devoting resources to stop them becomes counterproductive, and it would be better to devote those resources to more tractable problems.