The Queensland Law Society, the state's peak body for solicitors, called on Mr Newman to reconsider his comments, with president Ian Brown describing them as deeply concerning.
"It is entirely inappropriate to suggest that, as a profession, solicitors are, for want of a better term, hired guns," he told AAP.
"Comments such as 'lawyers or solicitors are hired guns' and that 'solicitors will say and do anything to defend their clients', those kind of comments relate to the entirely of the legal profession - solicitors and barristers alike."
Mr Brown said the premier's comments undermined the legal assumption that someone was innocent until proven guilty, adding that this implied solicitors were breaching their fundamental duty to the court.
Peter Davis, the president of the Queensland Bar Association, also took a swipe at the premier, saying his comments were "misconceived, unfair and objectionable".
"Defence lawyers play an important and integral role in the administration of justice ... ensuring fairness and justice to those so accused," he said in a statement.