Trust like the topic goes, is it even possible to do that? We must have seen movies or heard stories that have to do with FBI or CIA agents, some computer-related gimmicks in an underground oval office, on the screen will be some kind of red circular lines fixed on some person, car or any form of a vehicle at all. Sometimes it comes in the form of a dotted red light in a tick-tag motion. Sometimes these victims that are being tracked have no idea what is happening, as in they have no idea their phones are being tracked, a stimulation that raises a question as to is it illegal to perform such action without the owner knowing? Well, it depends because in some situations trading one's phone without his/her consent can actually save the owner’s phone without his/her consent can actually save the owner’s life while on the contrary, it can do otherwise. So it depends on the reason behind tracking the first place.
Imagine a situation where someone is being kidnapped and an ultimatum is given, taking the legal path to acquire some sort of licence or document that allows the phone to tracked might just be a bad idea, whereas if you are in position to perform such action, the wisest thing to do is to go ahead and track that phone before it gets lates. The only situation where it will be illegal is when it is being used for obnoxious means which usually leads to crime.
Why you must not track phones without the owner’s consent
In some laws it is considered criminal and attracts a maximum sentence while the other attracts a maximum fine. Although it depends on where you are like; for US citizens, such action attracts 1 to 3 years in prison and it is tagged “C” Felony. But in a situation whereby it interrupts or intercepts communication, it attracts more intense punishment because it has to do with “violation of wiretapping law” which is supposedly a federal offense which has the possibility of landing in you a 20-year jail term.
In fact, there has been a case of a Dallas husband who tracked his wife’s mobile phone without her knowing it and even went as far as recording her phone conversations. when the wife later found out, she didn’t just go mad at the whole scenario, she sued the husband for infringement of privacy.