A detective who starred in Love/Hate will not be able to act as a garda again without the permission of the Garda Commissioner.
Two years after undercover detective Kieran O'Reilly first starred in the hit show, all officers in the force have been issued with the new directive from Garda headquarters.
There was major controversy when it emerged the highly-respected officer, who played the nemesis of gang boss Nidge in the RTE series, was facing disciplinary sanction for playing the role of undercover detective Ciaran Madden.
Garda management have changed the force's disciplinary code to prevent all serving officers from portraying the role of gardai or making references to gardai in fictional film and TV productions unless they are given advance permission by the head of the force.
Any garda who now acts as an officer in such a production without advance permission faces being disciplined.
Penalties provided under the regulations include dismissal, reduction in rank, temporary reduction in pay, as well as caution and advice.
The new change to the Garda code was issued last week. Sources have said that any future breaches of the new directive will be investigated by the force's internal affairs division.
Detective O'Reilly, who worked as an undercover drug squad officer for six years, caused consternation among the garda top brass following his appearance in two series of Love/Hate.
Former Garda Commissioner Martin Callinan ordered a disciplinary inquiry into the detective's involvement in the show. Senior management were furious and expressed concerns that the character played by Det O'Reilly was "too close" to his former work with the Garda National Drugs Unit.
However, it emerged that he was not in breach of any disciplinary regulations. Det O'Reilly has since been transferred to the Garda National Immigration Bureau.
In June of last year, Garda Commissioner Noirin O'Sullivan refused to comment when asked if she had given permission for Det O'Reilly to appear on the final series of the show, which he later did.
"We have very comprehensive policies around activities members of An Garda Siochana can't engage in if there is a potential conflict.
"If we have a member who is going to do something we would have to look at it and see where it comes within those prohibited spare time activities," she said at the time.
In March, Det O'Reilly appeared on RTE's Saturday Night Show where he said, "I was subject to a disciplinary investigation but that's all over now.
"I mean that was stressful but I'm very proud to be an officer and I'm happy being in the garda and it's finished."