SEATTLE — Washington state will have to pay significant sanctions after its expert witnesses deleted emails related to a lawsuit over liability for the deadly Oso landslide, a judge said Tuesday.

King County Superior Court Judge Roger Rogoff said Tuesday he needs more time to determine the amount of the sanctions, but will include costs the plaintiffs’ attorneys incurred because of the deletions, The Daily Herald of Everett reported ( ).

The judge denied the plaintiffs’ requests to decide in their favor without trial or to exclude testimony from certain state experts.

Rogoff said at least one of the state’s attorneys encouraged the experts to destroy records, and he wants to spur the Attorney General’s Office to overhaul its training practices.

“The fact that the public may be impacted by this may hopefully deter other problems in this area,” Rogoff said.

Victims of the slide, which killed 43 people, argue that the state and a timber company should be held liable for the landslide, based on the notion that their actions — including the construction of a sediment retention wall and logging — made the hillside more dangerous and failed to warn residents of the danger. Their attorneys say damages could top $100 million. Opening statements are set for next Monday.

Attorney General Bob Ferguson has already acknowledged that one of his lawyers, Mark Jobson, knew for the past year and a half that experts hired by the state to determine the cause of the 2014 slide were deleting emails among themselves. But the office insists that its other lawyers were unaware, and that Jobson and the experts sincerely believed the emails did not need to be turned over to the plaintiffs and thus could be deleted.

Rogoff said the evidence — including internal emails he required the Attorney General’s Office to produce — didn’t support Jobson’s explanation. The judge also said other lawyers representing the state may have been aware of the strategy to delete emails.

Ferguson’s office has been working with a computer forensic consultant to recover deleted records from numerous electronic devices used by eight people.

In his ruling, Rogoff said the Attorney General’s Office should have acknowledged the problem by December of last year, but didn’t until August, when attorneys for the plaintiffs discovered the problem and accused the state of fraud.

In asking the judge to punish the state, the victims’ lawyers argued that the experts tailored their findings to suit the state’s case and that deleting the emails helped them cover their tracks.

Information from: The Daily Herald,