If the purpose of these monitoring devices is that of facilitating more efficient traffic control I would voluntarily accept installation only if a law were passed making it a criminal offense (with a minimum one year imprisonment penalty) to employ or reveal the data it generates for any other purpose.
I am confident that proviso would prevent any bureaucrat from misusing or allowing misuse of the data.
Because we know the government can be trusted not to abuse access to information, right?
Geez, some people will never get it.