The Queensland premier, Annastacia Palaszczuk, has formally refused to provide any evidence to support her claims to parliament that climate change activists are using devices “laced with traps”.

Last month, Palaszczuk made the comments – along with social media posts saying protesters were using “sinister tactics” and intended to cause harm – as she announced new laws cracking down on escalating climate and anti-coal demonstrations in Queensland.

Palaszczuk told parliament she had been briefed by the police commissioner, Katarina Carroll, and shown evidence of devices used by protesters that contained fragments of broken glass and butane canisters.

Within hours of her announcement, questions emerged about whether the claims were true. Police believe “locking” devices can be dangerous but accepted their intent was to prevent the removal of activists during acts of civil disobedience.

The government has not provided evidence to support the extent of its claims about the actions and intent of protesters.

The state’s lone Greens MP, Michael Berkman, put several questions on notice to Palaszczuk, asking the premier to outline how many examples of such devices she had been made aware of, and the respective dates and locations.

Berkman also asked Palaszczuk to detail how, as she had claimed, the devices were designed to harm.

In her published response, Palaszczuk said she received a briefing “in relation to operational police matters”.

“It would not be prudent to publicly disclose the contents of that briefing,” she said.

Premier Annastacia Palaszczuk speaks in parliament. Photograph: Glenn Hunt/AAP

Berkman said he had requested a similar briefing from Carroll more than a month ago.

“What the premier described in parliament last month was really serious; that’s why I requested a briefing from the police commissioner so I could get the facts myself,” Berkman said.

“The premier used this briefing to justify introducing new criminal offences and expanding police powers. That’s not something that should be done without an incredibly good reason, but she can’t even give us one.

“If the government is no longer required to provide any factual basis for legislation we’re in trouble – particularly in a state where they can easily pass laws through our single house of parliament.”

Last week, the state government tabled draft legislation to outlaw “dangerous attachment devices”. Explanatory notes revealed the government had sought the input of the mining lobby.

Environmental groups and other critics have grown concerned at the extent to which, since the May federal election, Queensland Labor has changed its rhetoric and sought to embrace the coal sector to shore-up regional support.

On Friday, the government cancelled a scheduled court hearing to prosecute Adani for allegedly providing false and misleading information – a case that environmental lawyers say could lead to the miner’s licence being revoked.

The Environmental Defender’s Office Queensland said the case illustrated the extent of the state’s pro-coal pivot; that it had prioritised its crackdown on climate protesters over efforts to ensure mining companies complied with the law.

Since the prosecution against Adani was launched, the state government has announced new anti-protest laws, consulted with stakeholders, drafted legislation and tabled the bill in parliament.

“It’s beyond belief that peaceful protesters are ... focused on and treated harshly when the government should be turning their attention to these big mining companies, the impacts of their coal and to making sure they comply with the law,” the EDO Queensland solicitor and chief executive Jo-Anne Bragg said.

“[The delay] says that the government doesn’t prioritise enforcing the law against big mining companies whose projects have huge and unacceptable climate impacts.”