A "volunteer", in relation to a forensic procedure, is a person—
(a) who volunteers to a police officer to undergo the forensic procedure; or
(b) if the person is a child—whose parent or guardian, on the child's behalf, volunteers to a police officer that the child undergo the forensic procedure; or
(c) if the person is an incapable person—whose parent, guardian or close associate, on the incapable person's behalf, volunteers to a police officer that the incapable person undergo the forensic procedure.