If we are talking stats, lets stay with general principles.
The greatest majority of school shooters in the US are by Caucasian's living in rural/suburban areas. Shooting up schools is not common for Caucasians living in rural/suburban America.
There are 2 million people in US prisons.
Possibly 600 thousand have BPD.
There are 18 million people in US with BPD.
That is 3% of people with clinical BPD (6% if you use the incidence reported in the study).
If we look at our population here, 60-70% are below clinical thresholds... .
That would be 1% of our members partners. (2% if you use the incidence reported in the study).
Apologies Skip i should have said not uncommon,
and due to socio economic and other reasons are undoubtedely way under represented on this board,
the figures above also only look at those in prison currently and not those who have subsequently been released,
As a whole if you randomly picked someone who is clinically BPD it would not be surprising if they had been incarcerated at some point.