-Support
No, it makes no sense in role play that you will be able to whip out a phone while handcuffed, and contact people. (Phone being used as an example to /advert or /pm) Your hands are literally behind your back, and to add onto that, if you want "roleplay" you most likely would be searched, and your phone would be with the officer, and there's no way they'd willingly let you call for backup.