EVERETT — A judge must decide whether there is sufficient evidence to bring a Lake Stevens man to trial for a fatal crash early last year after a test found methamphetamine in his blood.

Todd Eugene Brown, 52, is scheduled for trial in late April, charged with two counts each of vehicular homicide and vehicular assault.

Brown was driving his employer’s Ford F-250 when it became embedded inside the back of a minivan that had slowed for traffic along the northbound lanes of I-5 near Lynnwood. Prosecutors say there was no indication Brown attempted to brake.

The van was carrying two adults and four children, all relatives. Killed in the Feb. 3 crash were Amiyah Johnson, 12, a sixth-grader at Olympic View Middle School and her cousin, Yesterday Wallace, 2. Two boys, ages 5 and 7, were hospitalized with numerous broken bones.

The crash was a criminal act because Brown’s driving was impaired by meth, prosecutors contend.

Brown’s attorney, longtime public defender Caroline Mann, on Friday urged Snohomish County Superior Court Judge George Appel to dismiss the charges.

Prosecutors won’t be able to prove her client’s driving was affected by the drug at the time of the crash, in part because there is no solid data to demonstrate how methamphetamine affects different people, she said.

Moreover, Brown was not arrested after troopers conducted field sobriety tests at the scene.

She said the case against her client would require jurors to reach a verdict based on speculation and inference.

“The fact that there was an accident is not proof that Mr. Brown was under the influence,” she said in court papers filed ahead of Friday’s hearing. “Accidents happen all the time without drugs or alcohol being involved. No witnesses observed anything unusual about Mr. Brown’s driving, or saw anything that what happened was anything other than a tragic accident.”

It’s not that simple, and the record is clear there were reasons for suspicion from the outset, deputy prosecutor Tobin Darrow said.

Troopers did note that Brown exhibited some symptoms of impairment, including balance problems, bloodshot eyes, eyelid tremors and diminished ability to gauge the passage of time.

A trooper trained to spot signs of drug use testified Friday that was one reason he asked Brown to submit to a voluntary blood test — to clear up any questions.

Brown agreed, after speaking with an attorney. He had denied using drugs or alcohol prior to the crash. The test detected meth at a concentration considered about double what is typically seen in people who are using the drug for recreational purposes and 20 times the amount that would have been present if Brown had been prescribed the compound for some therapeutic reason, Darrow said.

Under the law, prosecutors only need to demonstrate Brown’s ability to drive was “lessened in any appreciable degree,” the prosecutor said.

The dynamics of the crash shed some light, Darrow said.

Brown has maintained that traffic was stopped when he crashed into the van. Witnesses say otherwise. Analysis shows his truck was traveling at least 20 mph faster than the van when it slammed into it from behind. The combined wreckage of the two vehicles traveled more than 100 feet after impact, the prosecutor said in pleadings filed before the hearing.

“Although the weather was poor, it was daylight and the fact the defendant failed to appreciate his own speed being too fast for conditions, and his failure to brake or make any effort to avoid the collision can certainly be reasonably inferred to have been at least partly caused by being affected by his use of methamphetamine,” he added.

The judge said he expects to announce his ruling late next week.

Scott North: 425-339-3431; north@heraldnet.com. Twitter: @snorthnews.