Mackenzie Shirilla's dad was in full damage-control mode after her arrest ... repeatedly warning police not to question his daughter.

Body cam footage, obtained by TMZ, shows Steve Shirilla arriving at the Strongsville Police Department shortly after Mackenzie was arrested in November 2022 in connection with the crash that killed her boyfriend, Dominic Russo, and friend Davion Flanagan. Check out the video ... Steve yells about cops supposedly not being allowed to question his daughter as he demands to see her immediately.

At one point, an officer reminds him Mackenzie is legally an adult and can speak for herself. Steve's response? "Yeah, but she's a dumb 18-year-old."

The tense exchange continues as Steve blasts investigators for arresting Mackenzie publicly instead of asking him to bring her in ... and even accuses cops of having someone watching his home. Officers repeatedly explain they can't allow him access to his daughter and that Mackenzie would need to invoke her own constitutional rights if she chose not to talk.

The footage is resurfacing as interest in the case spikes following the release of Netflix's documentary, "The Crash." As TMZ previously reported, Steve was placed on paid leave from his Catholic school teaching job after comments featured in the documentary sparked backlash. He later told TMZ the film took his remarks out of context.

Mackenzie was convicted in 2023 of multiple murder charges tied to the deadly crash and is currently serving concurrent sentences of 15 years to life. She's eligible for parole in 2037.