He will supervise the selection and handcuffing .

他将监督挑选和上手铐。

Rear handcuffing is normally reserved for violent offenders , or is sometimes used where police have no knowledge of the person arrested and cannot guarantee their safety .

后方手铐通常是预留作暴力罪犯，或有时被用于何处，警方已不知道被逮捕的人，并且不能保证他们的安全。