A Liberal MP and former minister under Mike Baird has launched a scathing attack on his government’s decision to spend $2.5 billion on sporting stadiums, questioning how it could be justified when their performance in child protection has been a “disgrace”.

Matthew Mason-Cox, a former fair trading minister, said it was a damning indictment of the current system that “a couple of sporting stadia [can be prioritised] before the welfare of the most vulnerable children and families in our community”.

“It’s a no brainer as far as I’m concerned,” Mr Mason-Cox, an upper house MP, said.

Liberal MP Matthew Mason-Cox is the first government MP to publicly oppose the stadium decision. Credit:Samuel Groves

“At this point in time we are still waiting to hear from the government about whether there is a business case for the stadia, we don't know whether that actually stacks up, all the evidence points to it being difficult to justify [and] the party room hasn't been informed as to where exactly things stand," he said.