Government keeps Roe 8 details hidden

The Turnbull government has not complied with a senate order to release documents about the largely federal-funded Perth Freight Link.

It was motioned by WA Greens Senator Scott Ludlam on September 1 and included providing an estimate of financial penalties the Barnett government could expose WA taxpayers to should project contracts be terminated.

The road aims to divert heavy trucks onto a direct route to Fremantle Port and will be the state's first toll road, but has many opponents on environmental and Aboriginal heritage grounds.

The Labor opposition has vowed to axe the project if it wins the March state election, but has stopped short of saying it will tear up contracts.

Senator Ludlam said the Turnbull government had offered a flimsy excuse for keeping details of the project hidden from the public.

"The government seems to think the public are better off not knowing the extent of their liability for termination of contracts," he said.

"The further we go along this path of signing contracts and bulldozing bushland, means more wasted taxes for no results.

"The sooner Labor commit to ripping up the contracts, the (sooner the) ball will be in the Liberal's court to cease signing contracts."

The motion, backed by the senate on Monday, includes compelling the government to release correspondence relating to traffic modelling and meetings between ministers and the successful tenderer, major Liberal Party donor Leighton Holdings.

It cost Victorians $642 million to unravel complex contracts signed by the Napthine government for the East West Link, which Senator Ludlam says is because Labor took so long to announce its intention, allowing the Liberals to continue to sign contracts.

"WA Labor need to get off the fence and commit to tearing up the contracts," he said.

"We'll keep trying to force some transparency."