After a 30-year interval, shackled gangs of convicts have lately reappeared on the public highways or stone quarries of half a dozen US states - sop to an angry public's insistence that criminals are not only punished, but are visibly humiliated as well. Hitherto, however, prisoners have been chained in the traditional way, either to each other, or individually by the ankles with a chain too short to allow them to run. Armed guards make sure the men do not fight or attempt to escape.
Soon, however, this technology may be obsolete. Starting next month, the prison authorities in Queen Anne's county, Maryland, 50 miles east of Washington, may send out chain gangs controlled not by metal fetters but a fearsome device called a stun belt, that leaves its victims writhing on the ground in agony.
Fitted to individual prisoners, the belt comes with two prongs and a battery. From 100 yards away a guard merely has to push a button to send a 50,000 volt surge for up to eight seconds through a prisoner's body. A very low amperage means the charge is not fatal. But it incapacitates for up to 10 minutes, completely overriding the neuro-muscular system and causing loss of control of bladder and bowels.
Stun Tech Inc, the Cleveland firm which makes them, has already sold 1,100 belts to prisons and the federal marshals service, and so dreaded are they by prisoners that they have been activated on only 14 of the 30,000 occasions they have been worn.
Amnesty International and other human rights groups have tried to have the belts banned as "cruel, degrading and inhuman" and possible instruments of torture, but in vain. Not only do stun belts work, they also save money. Though they cost $600 to $700 (pounds 375-437) apiece, the reduced need for guards more than recoups that outlay.