The NRL has declined to respond to criticism over Willie Mason's two-match suspension for a shoulder charge, believing the Manly prop's decision to plead guilty indicates he now accepts the tackle is illegal.

However, the controversy over the shoulder charge continues after the brother of James Ackerman - the Queensland Cup prop who died seven weeks ago - hit out at leading commentator Peter Sterling for refusing to condemn the tackle.

James Ackerman, 25, pictured here with children Olliver and Milly, died after being injured in a tackle in Queensland in June. Credit:Facebook

Andrew Ackerman, whose heartfelt post on Facebook about why the shoulder charge should be banned last week prompted Sonny Bill Williams to offer his support, said he wanted the debate to stop and would continue to publicly criticise Sterling over the issue.

"I am just not happy with him continuing to back the shoulder charge after what has happened," Ackerman told Fairfax Media. "He is entitled to his opinion but he is being disrespectful to my family and I by bringing this up. If he continues to disrespect my family and James I will keep the posts coming.