Home Invasion or Prank?

[MechAg94]

In Texas, we have pretty good legal cover once someone enters the home.  I have heard the door could be wide open and you still have that cover. 

There have been cases of people shooting through doors.  The case I remember involved a drunk at the wrong house beating on the door and making audible threats. 

[Northwoods]

No matter the jurisdiction there are 4 (and in some places 5) elements of self defense you must satisfy to claim legal self defense in a deadly force incident.

Innocence - you cannot be the aggressor
Immenance - the threat must be in the moment, not some theoretical future threat, or a threat that has retreated.
Reasonableness - you must have a subjective belief that you are facing deadly force harm, and an objectively reasonable person must agree with that assessment
Proportionality - you cannot use deadly force in response to non-deadly force.
Avoidance - in some jurisdictions you must show a good faith attempt to retreat and avoid the situation. Thankfully there are only a few states that require this.

Many states give a statutory presumption of the first 4 elements when facing an invasion of your home or vehicle.  However, there are definitions of invasion that must be satisfied to invoke those presumptions.  This case will probably hinge on whether or not the teens actions gave the homeowner those legal presumptions of lawful self defense.

[MechAg94]

Good summary.

Some states allow "risk of serious bodily injury" as an additional justification for deadly force.  I would say there generally needs to be some size difference or actual injury to make sure that one sticks. 

[Northwoods]

Good summary.

Some states allow "risk of serious bodily injury" as an additional justification for deadly force.  I would say there generally needs to be some size difference or actual injury to make sure that one sticks. 

Deadly force harm includes risk of great bodily harm.

[MechAg94]

Deadly force harm includes risk of great bodily harm.

Depends on who you ask.  My understanding is not all states allow that. 

It is specifically stated in Texas law as threat of death or serious bodily injury.  There was a much talked about self defense case soon after our license to carry law started where a guy shot a man who was wailing on him with fists after a minor traffic incident.  He was acquitted since "serious bodily injury" could be caused by fists. 

[Northwoods]

Depends on who you ask.  My understanding is not all states allow that. 

It is specifically stated in Texas law as threat of death or serious bodily injury.  There was a much talked about self defense case soon after our license to carry law started where a guy shot a man who was wailing on him with fists after a minor traffic incident.  He was acquitted since "serious bodily injury" could be caused by fists. 

Disparity of force can turn simple battery in a deadly force threat. 6'4" 230lb ripped young guy vs 5'2" woman, or elderly man, or similar.  2+ assailants on a lone victim.  Skilled fighter vs random dude.  Etc.

A simple fistfight usually won't qualify you to shoot the aggressor. But if they go to a ground-and-pound it's no longer a simple fistfight.  Once you're on the ground, unless you're a skilled grappler, and the assault is continuing, your life is very much in danger.