Jonathan Kroft says a suggested publication ban would allow "an unaccountable group of anonymous civil servants" to avoid scrutiny.
Child welfare agencies and the social workers union are asking for a ban on the identities of workers who are to testify at an upcoming public inquiry into Phoenix Sinclair.
"The true danger to children, and to all Canadians, would be to permit an unaccountable group of anonymous civil servants to make decisions ... without at some point being accountable personally to the public that they serve," Kroft said in his arguments Thursday.
"If the most important witnesses, who are government employees exercising discretion over the people of Manitoba's fundamental rights, and they are not identified, this is something other than a public inquiry," he said.
Sinclair was abused and killed in her home after child welfare workers took her out of foster care and returned her to her mother.
Lawyers for the union and child welfare agencies say identifying the workers involved would be demoralizing and make it harder to attract workers.
But Kroft said the workers need to be accountable.
"The applicants ... are government officials. They work for the government. They're paid by the taxpayers of Manitoba. And the people of this province have entrusted those people with the power to remove children from their parents."
Kroft told inquiry commissioner Ted Hughes that the groups applying for the publication ban "are asking you to withhold truthful information from the people of Manitoba."
Earlier in the day, a lawyer for one child welfare agency suggested that allowing reporters to name and photograph social workers at the hearing would harm the entire child-welfare system in Manitoba.
"The system is currently under strain. There's a lot of stress. And putting the system under further stress and individuals under further stress ... you're really putting the best interest of children at risk," Hafeez Khan said.
"(Staff) turnover is not in the best interests of the child. Turnover results in instability for children who are in care. We are already experiencing a high turnover rate throughout the ... system."
Khan represents Intertribal Child and Family Services, one of several groups asking for the ban in advance of the inquiry slated to start in September. Khan also echoed comments from the Manitoba Government Employees Union and regional child welfare authorities that media coverage of the inquiry will be unfair if social workers are named.
The inquiry is to examine how child welfare failed to protect Phoenix. She had spent most of her life in foster care but was returned to her mother, Samantha Kematch, in 2004. The girl suffered near-constant abuse by Kematch and the woman's boyfriend, Karl McKay. Phoenix died after a brutal assault in June 2005 in the basement of the family's home on the Fisher River reserve north of Winnipeg.
Child welfare workers had earlier closed the girl's file and decided all was well. A few months before she died, a social worker went to check on her and was told she was asleep. He saw a sibling playing outside who appeared healthy and decided that was enough.
According to evidence in the first-degree murder trial that led to life sentences for Kematch and McKay, Phoenix was frequently confined, shot with a BB gun, forced to eat her own vomit and neglected.
Her death went undetected for nine months, and Kematch and McKay continued to claim benefits in her name. Eventually, a relative called police and the girl's body was found in a shallow grave.
The lawyer for Kim Edwards, the foster mother who cared for Phoenix for much of her short life, will also argue against the ban.
Hughes is to render his decision on the ban next Thursday.