alt Hacker NewsHere are three examples involving physical surveillance, mining public data, and using data collected by a third party, respectively.
https://www.fox8live.com/2026/08/07/unchecked-overtime-nopd-...
https://niemanreports.org/mining-the-data/
https://gijn.org/stories/investigations-using-strava-fitness...
I expect a "but this case is different" type reply; it's almost always possible to make an argument like that.
They would do that as part of their journalistic investigations. Just like a private eye would also track people. The difference is motive.
But it's a big grey zone between some clear cut "black" and "white" cases. I don't know if prosecutors are using or will use the fact of surveilling law enforcement as a crime itself or as evidence for intent to commit other crimes.