The trickle of mitigating circumstances trying to understand the motive of the Army soldier who allegedly slaughtered 16 Afghan civilians last Sunday has turned into an avalanche over the past 24 hours.

According to a defense attorney retained by his family, and news reports of rumors, innuendo and perhaps some facts, Staff Sergeant X has a growing list of problems, some of which were beyond his control:

— He was suffering from marital strife.

— He was suffering from post-traumatic stress disorder

— He was suffering from a traumatic brain injury he got in Iraq in 2010.

— The Army inadequately tested him and permitted his redeployment despite those conditions.

— He’d been promised he wouldn’t have to go back to war after his third tour in Iraq.

— He was ordered to Afghanistan overnight for his fourth tour in December.

— He saw a buddy’s leg blow off hours before the massacre.

— He got drunk before leaving his southern Afghanistan post at 3 a.m. to kill 16 men, women and children.

Army mental-health and legal officials aren’t surprised by the expanding roster. That’s what defense attorneys do. And – to avoid the death penalty, which Defense Secretary Leon Panetta has said is possible in this case – proving only one of these extenuating conditions may be sufficient to keep him alive at Fort Leavenworth, albeit for life.

It’s also what reporters do, especially when the press lacks a name so they are unable to dig into the suspect’s childhood to see what role his parents, siblings, elementary-school teachers and fellow Boy Scouts may have played.

None of these excuse what happened, of course. But one thing is becoming increasingly clear: the Army, and its treatment of such allegedly mentally-ailing troops, is going to be on trial as much as Staff Sergeant X.