The man accused of causing a car crash that killed twin sisters from Oak Harbor on Halloween night 2013 is slated to go to trial next week.

Ira Blackstock, 55, of Oak Harbor, is facing two counts of vehicular homicide and one count of vehicular assault in Skagit County Superior Court.

Janeah Goheen, a 17-year-old Oak Harbor resident, died at the scene of the Oct. 31, 2013, accident on State Highway 20 near Anacortes; her twin sister, Janesah Goheen, was injured and died at Harborview Medical Center in Seattle.

Their friend and passenger in the car, Alysha Pickler of Oak Harbor, suffered a concussion.

The trial is set to start Tuesday.

Skagit County Prosecutor Richard Weyrich said the complexity of the evidence was partly responsible for the delay in getting to trial, which  is expected to last for two weeks. He said there was some difficulty in scheduling experts to testify.

Also, he said a computer module from Blackstock’s car had to be sent out east for analysis. It may have details about the speed of the car before the crash.

Under the charges, Blackstock is accused of driving in a reckless manner. Weyrich said he expects Blackstock’s attorney to simply argue that he wasn’t driving reckless, but that the crash was a tragic and unforeseeable accident.

Blackstock’s attorney, Tom Fryer of Bellingham, didn’t return a call for comment.

Toxicology results showed that Blackstock was not impaired at the time of the accident. Investigators initially reported that he may have been under the influence.

According to a report prepared by a detective with the Washington State Patrol, Blackstock was driving his 2006 Ford Mustang south on State Highway 20 from “Sharpe’s Corner” in Skagit County and “accelerated rapidly” as he approached the intersection at Gibraltar Road.

The car — which had near-bald rear tires — broke traction on the wet asphalt, began to fishtail side-to-side and crossed into the oncoming lane, according to investigative reports.

The Mustang struck an oncoming 1993 Acura driven by Janesah Goheen just after 5 p.m.

“The purposeful and reckless acceleration by Ira L. Blackstock caused his Ford Mustang to strike the oncoming Acura four-door close to the northbound fog line of State Route No. 20,” the detective’s report states.

Court records show that Blackstock was issued three speeding tickets in 2013.

Weyrich said evidence of the speeding tickets will likely not be admissible at trial.