Hello Kevin:  According to all I've read the man was accused of being a convicted felon in possession of a firearm which he had used to threaten the life of his girlfriend.  This reads like a serious situation.  The police had him isolated in the deplex with no "hostage" or direct and imminent threat to anyone.  They wisely (IMO) chose to not "storm" the apartment and force a possible armed conflict.  I certainly agree with that decision.  However, if I'm understanding things correctly, they left the scene with the intent of "arresting him later."  That makes no sense to me.  It may have taken time to negotiate his surrender, but it would have been time well-spent.  If, in fact, he had a gun and had threatened the girlfriend, it makes no sense to me to say, in essence, "Hey, we're leaving now....see you later."  It seems there's a lot of "middle ground" between "killing the guy" and walking away from the scene.......What do you think?  thanks, Gary