Some law enforcement entity in Germany wanted to install license plate reading cameras a few years back. It was defeated as it violates privacy rights. I only read about it because they are running a pilot program for real-time face recognition in Berlin. Discussing this, someone mentioned the failed attempt to read car plates.
The issue was that all faces (plates) are (were) identified and stored without probable cause.
Of course, that was in a country that is highly sensitive to such issues.