Most likely depends on local laws. Saw a claim that (a private person) releasing security footage here in Finland is illegal for example, though i'm not sure if it was about violating personal privacy or releasing footage they don't have permission to use (also not sure if the claim is correct), police obviously has right to release the footage in certain situations.
Same here in Denmark, we had a case a few years ago where a pretty big business had multiple break ins by the same guy and it was caught on video. The owner being frustrated over the lack of response from the police decided to release surveillance video to the internet of the criminal stealing from him, thinking it could lead to the guy being arrested.
Him releasing the footage was deemed illegal and he had to pay a not insignificant amount of money in fines for doing so, it violated the privacy of the criminal and thus only the police may release such footage.
Edit
Reading up on the case again(it happened nearly 10 years ago), the company actually got the case dismissed since the courts ruled that the thief wasn't immediatly recognizable in the release footage. Guess I remembered it wrong.