Research suggests that most mass shootings are at their core suicidal acts, and new findings linking gun violence, suicide, and seasonality add support to that theory.
The new study led by a Harvard Medical School clinical fellow in medicine at Brigham and Women’s Hospital shows that annual peaks for mass shootings and suicide occur within days of each other in late June and July. Annual low points for both occur in the winter months, between December and February.
Mark Czeisler, lead author of the paper and also a resident physician at the hospital, said the link described by the study can inform medical and public health efforts. For instance, screening for suicide and gun violence can be enhanced as summer approaches, along with preparations to ensure health systems are ready to respond to violent events.
The findings, published in the Journal of Biological Rhythms, also raise questions about the nature of the connection between suicide, mass shootings, and seasons, especially as they mirror seasonal variation in depression, which has long been shown to peak in winter months.
What the work does not do, Czeisler said, is establish causation. Just because two variables peak at the same time is no guarantee that they are linked, he pointed out.
