SEATTLE — The attorney representing a coalition of parents and education groups that sued the state over school funding told the Washington Supreme Court on Wednesday that it should hold the Legislature in contempt for not obeying its orders.

Thomas Ahearne said the court should send lawmakers back to Olympia to finish their work.

“We’re asking the court to at least hold the Legislature in contempt, to prohibit any more unfunded or underfunded mandates on our schools, and to impose even more serious sanctions if the Legislature does not reconvene and obey the court’s orders by Dec. 31 of this year,” Ahearne wrote.

The Supreme Court’s 2012 McCleary decision said lawmakers are not meeting their constitutional responsibility to fully pay for basic education, and they are relying too much on local tax-levy dollars to balance the education budget.

In January, the Supreme Court ordered the Legislature to make immediate and real progress this year toward fully funding the state’s public schools and create a plan for completing the work by the 2017-2018 school year.

The Legislature made its required annual progress report to the court a few weeks ago, focusing on the ideas they discussed during the 2014 session for improving the way the state pays for public schools. Few of those ideas made it to the governor’s desk.

In his written response to the Legislature’s report to the Supreme Court, Ahearne said lawmakers do not seem to understand that the Supreme Court was issuing an order, not making a suggestion.

“The State did what it had been ordered to not do. It offered promises about trying to submit a plan and take significant action next year — along with excuses for why the State’s ongoing violation of kids’ constitutional rights and court orders should be excused this year,” he wrote.

It’s time for the court to compel the Legislature to follow its orders, Ahearne said. He went on to explain over 57 pages why such action would not violate the separation of powers, as some lawmakers have argued.

Powers are separated, he wrote, to ensure citizens the protection of an independent judiciary.

“As this court has long recognized, if a court does not enforce its orders and judgments, ‘it would then be nothing more than a mere advisory body’,” he wrote, quoting from a Washington Supreme Court decision in 1958 called Keller v. Keller.