Queensland Attorney-General Jarrod Bleijie says the state’s electoral act could be made invalid if it’s not consistent with federal donation disclosures.

The Queensland government has blamed a legal problem for its decision to increase the amount of money that can be secretly given to political parties.

The Newman government has passed new laws that dramatically increase what people can donate to parties in the state without ever having to tell voters.

Under the old laws, donations of $1000 or more had to be declared to the electoral commission, but that’s now been increased to $12,400.

The change has been condemned by the Labor opposition, minor parties and independent MPs as a dangerous attack on transparent government.

But on Friday, Attorney-General Jarrod Bleijie said there was Crown Law advice to say the Queensland electoral act could be held invalid if it wasn’t consistent with the federal disclosure threshold of $12,400.

He said the state government believed the federal threshold should be lowered, and Premier Campbell Newman would write to Prime Minister Tony Abbott to encourage him to do that.

Mr Bleijie said the new laws meant any future change to the federal threshold – up or down – would automatically flow through to Queensland.

Government MP Chris Davis – who’s said he was sacked as an assistant minister partly because he raised concerns about the disclosure change – rose in parliament to say he simply could not support it.

He warned the government risked losing the trust of voters, and noted that as Queensland relaxed disclosure rules, NSW Premier Mike Baird was doing the opposite in calling for an urgent ban on political donations.

“The front door to government is the ballot box and elected representatives, and the back door is other forms of influence,” Dr Davis told parliament.

But Dr Davis wasn’t present when it came time for a vote late on Thursday.

Opposition Leader Annastacia Palaszczuk said past records showed that 95 per cent of donations to political parties were less than $12,400.

“That means only five per cent will now be declared,” she told AAP.

“For the rest, there’ll be no record whatsoever. Queenslanders should seriously question why the LNP has done this now.”

She vowed Labor would repeal the change if it was returned to office.

Independent Liz Cunningham told parliament voters would be questioning the government’s motives.

“I believe that the people of Queensland will find it very difficult to accept that such a great change is done without unacceptable motives,” she told parliament.

“An increase from $1000 to $12,400 does nothing but put questions in the minds of the people of Queensland that there is something that is unpalatable and unacceptable in the motivation for this change.”