The retired judge who oversaw the Phoenix Sinclair inquiry says the Manitoba government has rejected one of his key recommendations to improve the child-welfare system by making social workers accountable.

In his inquiry report, Ted Hughes recommended that social workers be required to register with a regulatory body similar to those governing the work of doctors and nurses.

But officials with the brand-new Manitoba College of Social Workers say their authority is being undermined by a government loophole that allows hundreds of workers — those who don't have the term "social worker" in their job titles — to avoid having to register.

That means hundreds of professionals who work with vulnerable children, including child protection workers and intake workers, would escape regulation, according to the college.

Hughes says anyone doing social work, regardless of their title, should be registered with the college.

"I guess they have the right to accept or reject my recommendations, but that one I think is clearly stated and the case for it has been clearly made in the report," he said in an interview.

Hughes said Family Services Minister Kerri Irvin-Ross had consulted him recently about some of his recommendations, but she did not discuss the registry of social workers with him at that time.

The judge added that he has already heard from some Manitoba social workers who are concerned that the new rules allow hundreds of workers to escape scrutiny and regulation.

"Under whatever title, whether it was a child-care worker or an emergency care worker, if they were indeed practicing social work, regardless of what their job description was or their title was, then they would be required to be registered," he said.

"The reason given in the report is this amendment will protect not only the title of social worker, but will ensure that members of the profession are truly qualified, meet a standard of competence and are governed by a code of ethics."

A provincial government spokesperson told CBC News it does not want child-welfare employees who are not qualified social workers to face mandatory registration.

The province's next steps will include reviewing workers' duties and determining with union officials whether more positions should be designated as "social worker" positions, the spokesperson said.

Hughes led the public inquiry looking into the death of five-year-old Phoenix Sinclair, who fell through the cracks of Manitoba's Child and Family Services system before she was murdered by her mother and stepfather in 2005.

After his report was released, the province pledged to overhaul its child-welfare system to keep more children with their families and home communities rather than taking them into foster care.