The Philly cop -- ID'd in the suit as Officer Burnett -- just got slapped with a lawsuit by Jacob Giddings ... the guy who claims his footage was scrubbed back in March while Burnett was trying to take him into custody on an arrest warrant.

According to the suit, obtained by TMZ, Giddings says he was pumping gas when Burnett ran his tags, identifying Giddings as someone who had a warrant out for his arrest. While Giddings was in his vehicle, he says Burnett approached him from outside ... asking him to step out of the vehicle without an explanation.

Things allegedly escalated from there. Giddings claims Burnett began trying to forcibly remove him from the car. BTW, Giddings says he had begun recording with his phone at this point ... feeling uneasy about the whole thing.

After a lot of tussling -- and the arrival of a 2nd officer -- Giddings says he surrendered, and was cuffed and put into the back of a squad car.

Giddings says Burnett then proceeded to search his car and found the phone that had been recording. Giddings makes a bombshell claim -- he says Burnett ran over his phone, with Giddings' own vehicle, in an attempt to destroy the evidence!

Giddings claims that after realizing the phone was STILL recording and not destroyed at all, Burnett then took it upon himself to delete the video -- only to play dumb when asked by Giddings if it was still on there. He's suing for assault, battery, excessive force and illegal search and seizure.

Of course, Giddings says Burnett's own body-cam was rolling during what Giddings says was the moment he tried getting rid of evidence ... and Giddings insists it's the smoking gun that proves his case.