Nightly News | January 05, 2012
>>> now to the story out of oklahoma about another mother forced to make an extraordinary step to protect herself and her child in a dangerous situation. intruders were at the door when she called 911. nbc's kristen dahlgren picks up the story.
>> reporter: a young mother facing a life or death decision.
>> i've got two guns in my hand. is it okay to shoot him if he comes in this door?
>> you have to make a choice -- you or him. i chose my son over him.
>> reporter: 18-year-old sara mcinially was home alone with her baby. grieving. her husband had died of cancer on christmas day when two men started banging on her door. grabbing a shotgun she called for help.
>> i knew she was scared. she was whispering. she didn't want him to know she was on the phone with me.
>> is it okay to shoot him if he comes in this door.
>> i can't tell you that you can do that. but you do what you have to do to protect your baby.
>> reporter: mckinley shot and killed justin martin who was armed with a knife.
>> they said i couldn't shoot him until he got in the house. he got in and i shot him.
>> reporter: she was cleared of wrongdoing, the 911 tapes showing she was clearly within the rights. a law in 21 states that gives the right to protect your home.
>> when someone breaks into your house the oklahoma castle law presumes the intruder intends to use deadly force so the homeowner is justified even if the intruder was unarmed.
>> reporter: the second alleged intruder is charged with first-degree murder.
>> the accomplice was up to no good. under our felony murder laws that's the person responsible.
>> reporter: today mckinley is a hometown hero with hope that the worst is behind her.
>> maybe something a little bit better than last year.
>> reporter: kristen dahlgren, nbc news, los angeles .