The state pathologist, Dr Jack Crane, told members of the justice committee his department could not dispose of any human body parts held as part of criminal investigations without instructions from the police, on 7 June 2012.
Dr Crane was briefing the committee on the retention of human tissue.
Sinn Fein's Raymond McCartney quoted evidence given to the committee by Assistant Chief Constable George Hamilton of the Police Service of Northern Ireland (PSNI) to the effect that the police were not involved in the destruction of any human material.
The state pathologist told Mr McCartney that his department could not destroy any human tissue retained for evidential purposes without police instructions as "we don't have the authority".
A number of committee members raised questions about a helpline set up in 2002 for families who were concerned that their loved one's tissue may have been retained without their knowledge.
Dr Crane said the helpline received around 300 calls.
Committee chairman Paul Givan of the DUP asked why it was left to the public to make enquiries.
The pathologist said his understanding was that "a number of families would not want to have this information".
Sinn Fein's Raymond McCartney asked about examples of tissue being retained without the knowledge of the family, and subsequently being destroyed.
Dr Crane explained that the Human Tissue Authority currently advised that if there was no reply from the family after three months "you should dispose of the tissue".
Democratic Unionist Sydney Anderson asked what the reaction had been from families when they were told tissues had been retained without their knowledge.
"Some were angry, some accepted it," the pathologist replied.
Mr Givan asserted that the state had "assumed rights that never belonged to them", and called for an inquiry.
The committee also heard from representatives of the Police Ombudsman's Office on human tissues that it had retained without the knowledge of families.
Peter O'Sullivan of the ombudsman's office told members they had retained seven samples in connection with four people.
He apologised for "the upset and anguish each family has suffered".
Paul Givan questioned the timing of the ombudsman's public announcement that it had held a number of human tissues.
This announcement was made on the day police and Department of Justice officials had appeared to brief the committee on body parts held by the PSNI.
He said a cynic would say the ombudsman's office wanted to get the news out "while the police were in the frame".
The committee chairman asked Mr O'Sullivan if the episode had brought the police ombudsman into disrepute.
Mr O'Sullivan said that was for others to judge.
Peter Weir of the DUP asked what was the flaw in the system that had allowed this to happen.
Mr O'Sullivan said the office had an old computer system and there was no proper tracking system for samples.
Before 2008, he explained, "we very much relied on human memory and human checks and balances".
The committee agreed to write to the Justice Minister to ask how he intended to proceed.