My husband and I are in the process of separating but still live in the same household right now. He is the only other person that has access to my car.
I have moved your question from general practice to Divorce and Separation. The reason, is your statement that you in the process of being separated. What this leads me to believe is that, your husband, or their attorney has hired a private investigator to monitor your activities.
The other possible causes for the GPS tracker other than your husband: Police investigation of either you or your husband, stalkers, mistaken identity.
Either way, I would consult with your divorce attorney, if you do not have one, you might want to get one quickly.
This is not uncommon in divorces, especially if one spouse suspects the other of adultery, or is otherwise a control freak and want to know everything about you. This would lead me to believe that ALL of your activities--cell phone, laptop, pc, email and social accounts--are being tracked with spyware. This is a legal gray area, and may or may not be legal, and the use of the evidence may or may not be admissible. Issues of invasion of privacy, stalking, harassment, etc., are all implicated. I would consult with an expert to review all your electronic devices for spyware and change all your passwords--better, obtain all independent accounts and cease using any shared accounts even if you have your own password, as administrator authority on the accounts often has the ability to obtain other shared user's passwords. If you do not already have a divorce lawyer, hire one. If your husband has been abusive in the past, and may be in the future, consider obtaining a domestic violence protection order, or filing for a limited divorce and requesting injunctive relief in that proceeding immediately (judges in divorce cases can issue any order they deem appropriate to protect a spouse from the abusive actions of the other spouse). In order for police to place such a device requires a search warrant from a judge.
I'm not aware of any law that makes putting a tracker on your car illegal, assuming that your husband had legal access to your car at the time that he placed the tracker on it. In other words, if he put the tracker on it when the car was parked at your and his home, and he did not have to break into anything to put the tracker on it, then that is probably okay. A tracker does not record anything except your location. Such information could also be gathered by a private investigator or by another witness, which is completely legal. So my educated guess is that using a tracker to record your location is also legal. Whether the information from the tracker is admissible in court is another question because the court may not assume that the information from the tracker is accurate or reliable.
Years licensed, work experience, educationLegal community recognition
Peer endorsements, associations, awardsLegal thought leadership
Publications, speaking engagementsDiscipline