Garda Brian Hanrahan told his armed mugger to "go f**k yourself" before the gunman opened fire on him and shot him twice, according to a police report.
Mr Hanrahan (30) was holidaying in New Orleans with his father when the incident happened last week.
The local police report into the shooting shows certain details which had been unknown until now, including how a barking dog alerted its owner to the crime and may have saved Brian's life.
Brian remains in intensive care in hospital with his wife Emma by his side but it is hoped he will make a full recovery after being shot in the body and leg.
New Orleans Police Department (NOPD) officers attached to the city's Fifth District received a call about the shooting in the Seventh Ward at approximately 5.40am on January 27.
"When officers arrived, they found the 30-year-old male victim lying in the driveway of a residence with multiple gunshot wounds to the body," a NOPD statement said.
According to the report, details of which appeared in The Star, the officers saw a bullet wound in Brian's lower left chest and another one on the inside of his upper right thigh.
"The victim stated an unknown black male approached from an unknown direction and asked the victim for money.
The victim replied 'go f**k yourself'," the report said.
"The suspect stated 'You think I'm playing?' and then shot the victim," it added.
The report also said that officers asked Brian if anyone else was involved and he had reported another unknown man hanging around him for around 15 minutes.
After being shot a woman had heard her dog barking repeatedly and went to see what was wrong and she discovered Brian injured in a neighbour's driveway and called police.
Police have now released photofits of the two suspects and named one as Melvin Galle Jr., a 40-year-old black male.
They have issued an arrest warrant for the man for attempted murder and armed robbery.
New Orleans Police Department detectives are now asking for the public's assistance in locating and identifying the second suspect, the alleged shooter.
They have released a colour composite sketch of the man and are offering up to $2,500 for information on the two men.
According to the police description, the gunman is a black male, aged in his late 30s or early 40s.
New Orleans Police Department have also released CCTV footage of two men seen in the same block on the morning of the shooting.
Garda Hanrahan is recovering well and has undergone surgery to remove a bullet from his lower spine. His wife Emma Holland, who is also from Killenaule, Co Tipperary, his mother Rose and father Brian Snr are daily visitors at the ILH-Interim LSU Hospital.
Over $5,000 has been collected by various local police departments and agencies to go towards any travel costs or medical bills on behalf of the Hanrahan family.