GPS stands for Global Positioning System, a signal that is forwarded to a computer that monitors the defendant’s locations every minute within a radius of a few feet. The ankle bracelet will detect any attempt to remove it or even to be without normal human movement, suggesting that it has been removed.
GPS electronic monitoring is used after the first appearance in court for defendants accused of domestic violence. Typically they are released with an exclusionary zone where the victim lives and works.
GPS can also be used after conviction along with house arrest as a substitute for time in jail. This option is particularly populer during the COVID-19 pandemic as an alternative to incarceration.