Abstract
The ability of juridical authorities to impose upon offenders electronically monitored curfews by means of personally worn ‘tags’ has been technically available for longer than two decades. Such a facility has been taken up on an increasing scale in North America, Britain, continental Western Europe, Australasia and Singapore, and is spreading. To this option, GPS satellite technology is now adding the yet more significant feasibility of round-the-clock surveillance and regulation of an offender's movements in the course of regular daily life, thus providing the technologically advanced world with the first ever effective alternative to the function of incarceration.