A complaint has been filed by the anti-surveillance advocacy group Privacy International against the U.K. Home Office, which is rolling out GPS tracking devices for migrants entering the country through irregular routes. Privacy International says the practice is excessive, unlawful and threatens the fundamental rights to privacy to which everyone in the United Kingdom is entitled. 

“These are just individuals who are seeking a new life in the U.K.,” said Lucie Audibert, a lawyer at Privacy International. “And so the necessity of surveilling them and monitoring in this way is highly questionable, and I question the effectiveness of it as well.”

The devices, which are bulky ankle bracelets of the same type that have been used in the criminal justice system for decades, monitor migrants’ movements 24/7. Anyone who is on immigration bail in the U.K. can be tagged, for an unlimited amount of time. 

The Home Office unveiled a new 12-month pilot to experiment with tagging people arriving on small boats in June, when Prime Minister Boris Johnson said migrants couldn’t be allowed to simply “vanish” into the country. The Home Office have said they intend to use the tags to stop migrants bound for offshore detention centers in Rwanda from disappearing — despite absconding rates being as low as 1% in 2020, according to a Freedom of Information request by Migrants Organise.