People gotta stop spreading this myth, they do this because the cars will overheat. The Chevy Tahoes specially being a K-9 Car is part of it. Due to being a K-9 Car they need to have their A/C on the whole time at full blast to keep the dog cool and alive. This will heat up the engine a significant amount, so they open the hoods to release heat and prevent the car from damage. Also note how they have the heat covers in the windshield to not heat up the interior.

Snopes also did an investigation in this when it first became an “issue” around 2016 and they also got the same answer.

There are obviously faults with police and security, but making up myths and lies hurts any truthful cases.