A cop who was racing to help Jim Irsay during the NFL owner's medical scare last month got a bit of an assist from Taylor Swift ... 'cause new police video, obtained by TMZ Sports, shows the officer was blaring the popstar's music as he rushed to the emergency.
The scene was captured on a Carmel Police Dept. dash camera at around 4:30 AM back on Dec. 8 ... just after cops say someone had called 911 to report Irsay might have suffered a possible overdose at his Indiana home.
In the footage, you can see that right after the call was received ... a policeman turned on his overhead lights -- and his Swift tunes -- to try to get to Irsay's house as soon as possible.
The officer blew through stop signs, at least one red light ... and swerved in and out of lanes -- all while "Cruel Summer" poured out of his vehicle's speakers.
At one point, the cop appeared to reach a high rate of speed as Swift could be heard belting out, "He looks up grinning like a devil, it's new!"
The cop also tuned in to Kenya Grace's "Strangers" ... before he finally arrived at Irsay's residence.
Several other members of law enforcement -- including at least three other cops -- also showed up to help render aid ... though according to their dash cams, they had no music on while en route to the scene.
Cops said in a police report they ultimately found Irsay in his bed gasping for air. They said he had a weak pulse as well as constricted pupils ... and he didn't respond to a sternum rub.
However, according to the police docs, Irsay did respond "slightly" after Narcan -- a drug commonly used in opiate overdose situations -- had been administered. He was later transported to a nearby hotel, where he survived. Cops classified the incident as both "overdose" and "overdose/poisoning."
On Jan. 9, over a month after the scare, the Colts announced Irsay was dealing with a "severe respiratory illness." They added in a statement last week that Jim was still recovering from his respiratory ailment.
"We will have no further comment on his personal health," the team said on Jan. 17, "and we continue to ask that Jim and his family's privacy be respected."