A New Mexico federal judge has ordered Facebook parent Meta to pay a $25 billion (£18.7bn) fine for mishandling the data of the state’s users and wilfully lying about its actions – while acknowledging that the financial penalty could have been nearly ten times larger.

The state filed the lawsuit in question in 2021, springing from Meta’s leak of user data to political consultancy Cambridge Analytica, a scandal that came to light in 2018 and preceded the company changing its name from Facebook to Meta.

In a September trial, a Santa Fe jury found Meta liable for more than 43 million infringements of the state’s unfair practices act, carrying a civil penalty of up to $5,000.

That meant the state was awarded a total of $219.5bn, according to a Wednesday filing.

New Mexico district court judge Francis Mathew acknowledged that the “highest level of penalty” allowed under the law was warranted, but reduced the fine to $25bn.

Judge Mathew wrote in the filing that the maximum penalty would have been justified due to “the extraordinary number of wilful violations found by the jury, the duration and repetition of the conduct, the breadth of subjects on which violations occurred, the involvement of senior Facebook leadership, the size of New Mexico audiences reached, and the clear intentional and systematic nature of Facebook’s repeated misstatements established in the trial record”.

He said interest on the fine would accrue at 15 percent until it is paid in full.

The judge said Meta had not carried out the “comprehensive investigation” it promised into the Cambridge Analytica imbroglio, instead executing a “wilfully ineffective” internal probe.

Factors contributing to this included “pressure from senior executives to keep costs down, lack of adequate enforcement resources, inadequate investigative techniques, and a desire not to create precedent for future investigations”, he wrote.

Meta resolved other Cambridge Analytica-related legal action in an August settlement with a coalition of state attorneys general, but New Mexico was not part of that settlement.

Earlier this year, a state jury also found Meta liable for child-safety violations and fined it $375m, followed by another $567m penalty in the trial’s second phase that determined the company’s actions created a public nuisance.

The company said it disagreed with that penalty and would appeal.