Georgia homeowner kills three masked teens during alleged robbery

A Georgia homeowner shot dead three masked teenagers in a possible "stand your ground" case, police say.

The teenagers allegedly tried to rob three people in the front yard of a home in Conyers and fired a handgun, prompting the resident to return fire.

The householder and young men, two 16-year-olds and a 15-year-old, have not been identified by law enforcement.

No charges have been filed yet. The homeowner involved has been taken in for questioning.

Rockdale County Deputy Lee Thomas said the teenagers were killed "during an exchange of gunfire". One was found dead when police arrived on scene, while the other two died at a local hospital.

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Police said the teenagers "had their faces covered as they approached the residence" and that one of the suspects "brandished a handgun and fired shots at the residents before one of the intended robbery victims returned fire".

The resident and two individuals with him were unharmed in Monday's incident.

WSB TV reported that the homeowner is a man and that he owns a semi-automatic rifle. One neighbour, Brian Jenkins, told the station he heard a man yelling during the incident, saying: "Help me, I'm dying".

Neighbour Carlos Watson told CBS News he heard "a lot of shots, and it was back and forth... it wasn't just one person shooting".

"I saw a gentleman laid out after I heard somebody scream for help," Mr Watson added. He said police "responded quickly".

Rockdale County Sheriff Eric Levett said when officers arrived on scene they found the masked young men lying on the ground and administered first aid.

"It could be a 'stand your ground' type case," Mr Levett said on Monday.

What is 'stand your ground'?

The stand-your-ground law in particular establishes the right for people to defend themselves, with lethal force if necessary, if they believe they are under the threat of bodily harm or death.

It overturns previous legal principles that dictate a person should retreat before using any force to defend themselves. But the law also states that legal protections cannot be given if the person instigated the altercation.

In Georgia, if the initial attacker retreats and is then shot at, stand-your-ground is not a solid defence.

A majority of states have some form of "stand your ground" law. Critics argue it has led to more shootings and has made it harder for some criminals to be prosecuted.

Opponents also believe that a racial disparity exists in the law's enforcement.

Three separate academic studies have concluded that white people are more successful at using stand-your-ground defences against black attackers, compared with the same situation vice-versa.

The law came under intense scrutiny following the fatal shooting of unarmed black teenager Trayvon Martin in 2012.