Under section 58(3)(b) JOSCs also have the option of establishing sub-committees in the same way as single authority overview & scrutiny committees.
O dan adran 58(3)(b), mae gan gyd-bwyllgorau trosolwg a chraffu hefyd yr opsiwn o sefydlu is-bwyllgorau yn yr un modd â phwyllgorau trosolwg a chraffu awdurdodau unigol.