I imagine it's stuff like these 2 articles linked in the op
https://apnews.com/article/gun-violence-science-health-covid-mental-20f5e2cb5fb50ff747fe316fdc4db5c4
https://apnews.com/article/violence-mass-shootings-summer-b004331ee7d3da95bce6646547f8d43f
The study shows gun violence rising, and that does include suicides. Though its most likely spurred on by the mass shootings mentioned in the second link. Taking those together explains the proposed measures.
Gross