evidential

Mr Cameron further told the hearing he anticipated "four to five weeks for the evidential hearings."

The CPS announced the charges against the former parliamentary researcher and teacher would be dropped early last week, as the "evidential threshold" had not been reached.

He said the families were "extremely concerned" about an evidential picture which indicated a "series of system failings, complacency, a lack of curiosity and inadequacy".

The watchdog said this "made it impossible to assess the evidential value of the information" but said a new process had since been agreed to share evidence.

Only four of the 12 people arrested met the evidential threshold to bring charges, according to the Crown Prosecution Service.