TAFE NSW has refused to release information about how much it paid for a controversial Boston Consulting Group report or the questions the government asked the consultants to answer.

The request for the  documents, made under freedom of information laws, comes after the NSW government promoted a private college network which the Australian Federal Police investigated for fraud.

TAFE NSW commissioned Boston Consulting Group to report on ways to make TAFE more efficient. It reported TAFE was uncompetitive compared to private education operator Australian Careers Network which collapsed and was the subject of police raids and allegations of fraud in April. 

The Boston Consulting Group report was released in April this year, a week after the ACN offices were raided. A spokeswoman for Boston Consulting has previously said the report was completed in 2015 using publicly available source material.

Greens NSW MP David Shoebridge asked for information about the report including its cost and the government brief given to Boston Consulting.

Despite being able to release relevant information, subject to some personal and private business information being redacted, the application was rejected because of Boston Consulting's objections to the information being released.

"Due to third party objections, other parts of the documents cannot be released until the end of the appeal period and the finalisation of any resultant action," TAFE chief operating officer Glen Babington said.

"I consulted with the affected third party and they objected to the disclosure of most of this information."

Mr Shoebridge said he was concerned the government had refused to release any information about how public money had been spent on the basis of the private consultants' objections.

"This is a private company that has produced a dodgy report on TAFE and they now want to prevent the public finding out how much taxpayer money they were given and what their riding instructions were," Mr Shoebridge said.

"Something is wrong in the state's FOI laws when a consulting firm can take countless thousands from taxpayers, deliver a highly partisan and flawed report, and then try and hide from public scrutiny.

"It is a fair question to ask whether or not Boston Consulting were given grossly flawed assumptions by the Baird government, or if they dreamed up their flawed comparisons on their own."

The Australian Consumer and Competition Commission has alleged the Australian Careers Network acted unconscionably by enrolling students with intellectual disabilities and people in Aboriginal communities who were saddled with $18,000 government loans.

The Boston Consulting Report said TAFE NSW's cost structure is "uncompetitive".

NSW Teachers Federation president Maurie Mulheron has criticised the Boston Consulting Report as a "flawed hatchet job".

"Boston Consulting Group is renowned as being hired guns to government to do a demolition job on public services," he said. "The report was released 15 months after it was written. It was a poorly researched and politically-loaded report."

A spokeswoman for TAFE NSW said it is processing a freedom of information application from Mr Shoebridge and has issued a decision to grant access to information.

"That decision is subject to legislated review rights of a third party that TAFE NSW is statutorily bound to observe," the spokeswoman said.

Boston Consulting Group declined to comment.