Gda Hanrahan is reported to have told his attacker to "Go f*** yourself" when he demanded his wallet. His attacker said: "You think I'm playing?" and shot him.
The shooting occurred in the early hours of the morning in an area of the city not usually frequented by tourists.
In March, it emerged that two brothers charged with shooting and robbing Gda Hanrahan are due to go on trial.
The garda was found by police at 5.40am on January 27, 2015, lying injured in the driveway of a house.
Melvin P Galle Jnr (40) and his brother Keith M Galle (33) were both charged with attempted second-degree murder and armed robbery.
Gda Hanrahan, a married father-of-two, required surgery to remove a bullet.
He had to spend time in hospital afterwards and his wife Emma and mother Rosemary flew over to the US to be at his bedside.
Originally from Killenaule in Co Tipperary, Gda Hanrahan told police that he met one of the suspects, who brought him to the area from the historical French Quarter of the city, telling the tourist that he knew where they could get a drink.
The victim said that he went to an ATM and withdrew $200 (€175).
When they reached the 2200 block of New Orleans Street, about two miles north of the French Quarter, a second man approached Gda Hanrahan and asked him for cash. When Gda Hanrahan refused, the suspect shot him, took his money and fled.
The medical care for Gda Hanrahan reportedly topped €900,000 and a number of fundraising events were held for him, including one at Limerick's Henry Street Garda Station.
His wife Emma Holland, who is also from Killenaule, and his parents were daily visitors at the ILH-Interim LSU Hospital.
Over $5,000 was collected by various local police departments and agencies to go towards any travel costs or medical bills on behalf of the Hanrahan family. The Irish community in New Orleans also raised funds.
Police had offered a $2,500 reward for information leading to the arrest of the suspects and attributed the apprehension of the men to "solid police work coupled with cooperation from the community".
The Galle brothers were arrested days later by police less than a mile from the scene of the shooting.