http://hsx.sagepub.com/content/early/2013/11/27/1088767913510297.full.pdf Lots of ammunition here (excuse the pun) for all sides. Highly encourage you to read the paper (it's not that long). Here's the dot-point version where I've highlighted the more contentious issues in bold: - Mass murderers very rarely just snap and start killing people. They plan for days, weeks or months. Random attacks are the rarest form of mass murder. - Witnesses to mass shootings often report that the perpetrators are calm, relaxed, and/or smiling. - Motives include: revenge, power, loyalty, terror, and profit. Revenge is by far the most commonplace motivator. [b]- Mass shootings and mass murder are not on the rise (see Figure 1 on page 5). However, the number of victims in each attack varies considerably each year.[/b] - Pervasiveness of technology which permits near-immediate reports in shootings has increased the public's fear, anxiety, and belief that the problem of mass shootings/murder is getting worse. - Media overexposure and obsession with "record-setting murder" has the possibility for an individual to identify, empathise, or admire a perpetrator. - There is little research of the "copycat effect" as it relates to mass murder, as it is mostly related to suicide. [b]- There is no hard evidence that mass murderers are drawn to similar crimes. They may influence them, but are not the inspiration.[/b] - The media should not obsess over "large and record-setting" body counts and avoid sensationalising sensational events. [b]- There is no causal link between consuming violent entertainment (ie. video games) and violent behaviour. (I realise this is already well known but at least you have something to point to now).[/b] - Mass shooters are most commonly: male, Caucasian, and older than murderers in general. They also share similar characteristics: depression, resentment, social isolation, tend to externalise blame, fascination with violent entertainment, and interest in weapons. However, the preceding characteristics are prevalent in the general population. - Profiling/checklists for mass shootings tend to over predict with a large number of false positives. - Aggressive attempts to single out potential troublemakers may make things worse. [b]- Greater access to mental health services may not work for individuals on the fringe. Those with the tendency to externalise blame see themselves and victims and the problem in others.[/b] [b]- If urged to seek counselling, a would-be mass murderer would likely resist angrily (because they don't see themselves as having a problem).[/b] - No clear relationship between psychiatric diagnosis and mass murder has been established. [b]- Most mass murderers do not have criminal records or a history of psychiatric hospitalisation, so they would not be disqualified from purchasing weapons legally.[/b] [b]- An examination of 93 mass shootings from 2009 to 2013 found no indication that any of the perpetrators were prohibited by federal law from possessing firearms. In only 10 of the 93 cases was there concern for the perpetrator's mental health that had been brought to the attention of a medical practitioner before the shooting.[/b] [b]- Several mass shooters have used firearms purchased, borrowed, or stolen from a family member of friend.[/b] [b]- The 1994 federal ban on assault weapons had virtually no effect on mass murders.[/b] [b]- The overwhelming majority of mass murderers use firearms that would not be restricted by an assault weapons ban, especially semiautomatic handguns.[/b] [b]- Limiting the size of ammunition clips would compel a gunman to pause to reload or switch weapons, potentially giving others a brief window of opportunity to escape or intervene. (This is backed up by two other sources)[/b] [b]- A study of the effect of right-to-carry laws and the incidence of multiple-victim homicide between 1977-1999 showed that right-to-carry laws neither encouraged nor discouraged mass shootings.[/b] [b]- It is hard to imagine that a vengeful student who is willing to die by police gunfire or his or her own hand would be dissuaded by knowing the faculty of a school were armed. They may even welcome the idea of a shootout with their teachers.[/b] [b]- It is ill-advised to encourage college students to carry guns on campus given the low rate of serious violence there and the high prevalence of substance abuse and depression among students.[/b] [b]- School shootings have an "exceptionally low probability of occurring" that excessive levels of security are not warranted.[/b] [b]- Most school security measures are a minor inconvenience for those determined to cause mayhem. For example, two middle school students pulled the fire alarm and waited for students to come outside before targeting them.[/b] [b]- Many schools, especially those in urban areas, already have security personnel, often equipped with firearms. However, school resource officers as a deterrent to mass shootings is too limited as they cannot be everywhere. For example, there were school resource officers at Columbine High School in 1999.[/b] - If armed guards or teachers really are a worthy strategy for protecting children, then this approach would dictate arming coaches, athletic directors, and even bus drivers to also protect them before and after school. (This appeared to be highly rhetorical in the text) Details of the paper:[quote]Written by James Fox and Monica DeLateur, both criminologists at Northeastern University. They received no funding for the research, authorship, and/or publication.[/quote]