The handcuffs are an item in Jailbreak, used to arrest prisoners or criminals.
Glitches
Prisoner/Criminal Glitch
There is a glitch in where a police officer puts a taser or handcuffs in a bed storage, and switching to prisoner, then grab it from the storage. Criminals and prisoners cannot use handcuffs.
Cannot Arrest
There is an occasional glitch in where you cannot use handcuffs.
Reloading Glitch
There is an occasional glitch in where after you use a taser, your handcuffs are reloading and therefore you cannot use them.