...before they need to prove cause for GPS tracking devices implanted in cars.

Leahy said the SJC ruling also means that police must persuade a judge they have probable cause before the GPS devices can be installed. He said that will be a barrier to widespread use by law enforcement.

“It’s good for the public, and it’s good for the rule of law,’’ Leahy said. “I don’t think it is currently a frequent law enforcement tactic. But the important point now is that it is much less likely to become a frequent tactic.’’

I guess that ALL depends upon the ethics and morals of the judge.