Late last week, a Wisconsin court ruled that its state police can track whoever they wish, suspect or not, without a warrant or even probable cause, using GPS. Eep.
The judge himself wrote, "police are seemingly free to secretly track anyone's public movements with a GPS device." Unsurprisingly, police are calling the decision a landmark victory for public safety, while the ACLU is up in arms about the invasion of privacy rights. Essentially, the judge ruled that it's not a violation of the fourth amendment (search and seizure) because the information gained could have been collected in some other way (like surveillance).
The ACLU is expected to make a big stink, and the case in which the ruling came down (a stalking case) is expected to see appeal, but it'd be a pretty scary precedent to set if the ruling is upheld. [Chicago Tribune via Crunchgear]