[ReaganIsRight]

If it's like mine the safety is part of the trigger. He probably caught the trigger while holstering it.

[justlurking]

He probably caught the trigger while holstering it.

Or he had his finger in the trigger guard.

[Myrddin]

If it's like mine the safety is part of the trigger. He probably caught the trigger while holstering it.

It is a very easy error to make with a Glock. Most of the holsters for Glock cover the trigger guard. If you leave your finger on the trigger while pushing the gun into the holster, the holster will shove your finger back into the trigger. The trigger pull is pretty light.