Representatives of the Children's Law Centre outlined their concerns about the proposed changes to the rules on DNA and fingerprint retention contained in the Criminal Justice Bill, on 4 October 2012.
John Patrick Clayton from the centre said their main objection was that "a caution is considered to be a conviction for the purposes of the bill".
He explained that a child who received cautions for two minor offences could have their fingerprints and DNA profile held indefinitely.
The DUP's Jim Wells questioned whether a child would be stigmatised by having DNA material retained.
The hearings on DNA and fingerprint retention continued with representatives from the Human Rights Commission (NIHRC).
Chief Commissioner Prof Michael O'Flaherty said they thought the bill went too far.
The professor said there was a right to privacy.
He also spoke of a "principle of proportionality", giving the example of a person convicted of TV licence evasion and a person convicted of murder being treated the same way.
The NIHRC wanted to see a process whereby a person who was aggrieved would be able to make an appeal to a court.
Jim Wells of the DUP was unconvinced.
"If I was thinking of committing a crime I'd be straight in there asking for it to be destroyed," he commented.
Prof O'Flaherty said it was not the role of the NIHRC to get involved in "psychological speculation".
The committee also heard from Patricia Lewsley, the Northern Ireland Commissioner for Children and Young People.