Portia Smith, 33, has called for justice as she plans her husband's funeral and prepares to give birth to their first child all in the same month.

Mrs Smith, of New Orleans, told NOLA.com that she was left heartbroken after her husband, Jonathan Smith, 31, was accidentally shot in the head by one of his childhood friends.

The couple, who first met in 2010, had been married less than a year before he was killed by 30-year-old friend, Christopher Lemley, who accidentally fired a gun he was admiring. The bullet hit Smith in the head.

Mrs Smith says that her husband was at Lemley's with her 17-year-old brother but when neither were home by 12:25am she texted Jonathan to see where they were.

Five minutes later, Lemley's wife called Mrs Smith with the shattering news.

"There's been an accident. Jonathan has been shot," Mrs Smith recalls Lemley's wife saying.

Mrs Smith said: "What do you mean? Is he OK? Where was he shot?"

"It's very bad. Just get over here," Lemley's wife said.

Mrs Smith arrived at the University Medical Centre New Orleans as her husband was undergoing surgery. She became so upset that staff admitted her to the hospital to monitor the baby.

While Smith survived the surgery he was declared brain dead and died two days later on September 19. His organs were donated to a dozen different people.

Lemley was arrested on September 24 and waived his right to silence, telling police he had held a friend's pistol and pulled back the gun's slide and squeezed the trigger while examining it.

He said he took a Percocet and had been drinking and that he doesn't remember firing the gun.

He was released on $US15,000 bail.

Mrs Smith wants Lemley is serve time for the crime.

"The actions he took that night were preventable and caused my husband's death and caused me to lose my best friend and Mila's father, whom she will never get to meet," she said.

According to a GoFundMe page set up to help Mrs Smith with unexpected medical bills, funeral expenses and her first child, the baby is due in three weeks as of September 17. So far more than $US6000 out of a $US10,000 target has been raised for her.