The four will join an existing nine volunteers as part of Gwent Police Authority’s Independent Custody Visiting Scheme.
The police authority and the force have said the scheme is vital in raising standards in custody and ensures the fair treatment of detainees.
Blaenau Gwent Councillor John Williams, who is the police authority lead member for the
Independent Custody Visiting Scheme, said: “I am extremely pleased that four new visitors have joined our scheme and am looking forward to everyone involved in the scheme working together to ensure that people in custody are receiving the right standard of care.
“Gwent Police is open to independent outside scrutiny and the public should be confident that the force is providing a high standard of custody arrangements.”