The NSW government is also accused of abusing its executive power in the committee's "scathing" report on toll roads released on Monday.
Cost of living pressures, including tolls, are expected to dominate the NSW election in March.
The upper house committee found NSW Treasury withholding contract and traffic details regarding WestConnex until at least 2060 was an abuse of executive power.
"If the government doesn't act, we will be asking the parliament to act and make it the law that this information has to be released," opposition roads spokesman John Graham said.
Committee chair and Greens MP Abigail Boyd says the government needs to take the inquiry's report seriously, as it waits on findings from its own review.
"The review that (the government) announced to pre-empt this scathing report will do nothing to address the hardships that we have identified here," she said.
Caps on tolls and appropriate flagfalls should be considered, the report recommends, in addition to Premier Dominic Perrottet's preferred distance-based tolling approach.
The rate at which tolls increase should also be reviewed, it said.
Other recommendations include toll relief for trucks and buses to get them off suburban streets, as well as an independent ombudsman funded by toll operators.
Liberal committee member Shayne Mallard told AAP on Monday the government was open to reform to "unscramble" the state's piecemeal tolling development by various governments over three decades.
He said the government rejects the 'abuse of power' finding and suggested it was motivated by a Labor party "hungry for election success".
"We don't support inquiries or committees attacking public servants doing their job," he said.
"The executive government will release the documents when it's appropriate ... that's not an important finding," he said.
He said rules were needed to stop people being laden with snowballing debt from unpaid tolls.
"Most of us pay our tolls when we go through but obviously some people fall on hard times ... we need to be really aware of that," he said.
The report recommended reducing administration fees when people use a toll road without an arranged payment.
The government should ensure Transurban reduces its fees to $1.10 for the first notice and $2.20 for the second, the report recommends.
Currently they are as much as $10 on top of the price of the unpaid toll, the same as it's been since 2001, which was four years before Transurban began operating toll roads in NSW.
Ms Boyd said that pricing is "predatory", and had sent one customer into $22,000 in debt on top of $8000 in unpaid tolls.
A Transurban spokesperson told AAP the operator is open to discussions, but any changes are a matter for the NSW government.
"A more equitable and efficient system would be the foundation of any discussion on reform," the spokesperson said.
NRMA spokesman Peter Khoury said the report presented opportunities to move on toll reform.
"What we need to start now is a reset of the partnership that exists with the private and public sector, to make sure that moving forward these roads deliver value for everyone," he said.
"The prices are all over the place now ... let's look at a standardised approach for pricing motorways and toll roads in Sydney," he said.
The NRMA has also called for an independent third party arbiter of contract negotiations between the government and toll road operators.
