IRVINGTON, NJ &#8211 One New Jersey policeman’s gift of gab could soon be the bane of his existence.

Officer Maurice Gattison, the Irvington, N.J., cop behind a profane-filled rap video recently posted to YouTube, is the subject of an internal investigation for making the wacky “gangsta rap” clip.

Police authorities are probing Gattison, the head of the Irvington police union, as well as three other township officers, to see if they broke any department rules in recording the gangster-style video.

Using the moniker “Gat the Great,” Gattison has reportedly filmed several rap videos, which feature the officer in a number of unusual situations, including one where he is behind the wheel of a car, sporting a lavish fur coat and fondling a thick roll of money.

One video, reportedly titled “Temper Like An Alcoholic,” features Gattison rapping about drinking and crime, using an anti-gay epithet and calling himself a “felon for life.”

“I wish (them) well, but still give (them) hell, they (are) fragile and frail. I make them feel me like brail. Yeah,” Gattison allegedly raps in one scene.

“So I bang (them) with a hammer. My grammar is impeccable. My flow is unorthodox and exceptional. I’m (letting) you in with this greatness, (so) take this as a lesson before you have to meet the Smith and Wesson,” he adds, before concluding, “What, ya’ll stressing? True confession, I’m a felon for life, don’t make me fruit-cup your melon tonight.”

In the video, the man rapping is seen pointing his finger at a camera as though he’s firing a gun. He’s also seen wearing jewelry, including gaudy rings on both hands, and driving around in a fancy car.

In another scene, a different man, bobbing his head to the rapper’s flow, is seen drinking from a cup that appears to have alcohol in it while clumsily swinging a mace — a medieval weapon resembling a heavy club with spikes on it.

While the video contains an offensive anti-gay insult as well as words that appear to promote criminal behavior, it doesn’t immediately appear that the rapper does anything illegal.

Whether he broke department rules, however, is another question.

“The Irvington Police Department has standards of conduct that apply to on-duty and off-duty behavior,” Police Director Joseph Santiago told the Newark Star-Ledger.

“Those standards have consistently been applied in circumstances where the officer’s private behavior undermines the police department’s position in the community or creates the impression that its members may not be able to fairly enforce the law,” added Santiago, who has until next month to file charges against the officers.

The situation has also sparked a debate over free speech and whether officers are bound by the same rules of behavior on- and off-duty.

Irvington Township Attorney Marvin Braker said the videos were disturbing but could be protected under the First Amendment.

For his part, Gattison said he’s been rapping for years and that he doesn’t quite understand what the big deal is.

“I could see if I was targeting somebody, but it’s just a lyrical exercise,” said Gattison, adding that he was even asked to perform at the police department’s holiday party.

View the video

From The New York Daily News