SNOHOMISH — A man charged with dragging a woman into some bushes May 3, ripping off her pants and attempting to rape her has been set free after continued police investigation turned up evidence suggesting he was in Eastern Washington at the time of the attack.

Paul Andrew Williams, 36, was arrested a few days after the woman told police she had been grabbed by a stranger around 3 a.m. as she walked to her job in Snohomish. The assailant pulled down her pants and was unbuckling his belt when she managed to kick him in the face and break free. Surveillance video captured the woman, 22, running from the scene partially clothed.

Williams, who lives with mental health challenges and often is homeless, resembles a sketch the woman helped police prepare of her attacker. He was arrested after she picked out his photograph when shown it as part of a montage.

Williams denied any involvement in the attack. At his first hearing in the case, he told the judge he had never met the woman.

“I want my case dismissed right now,” he said at the time.

Instead, he was ordered jailed on $500,000 bail and later charged with attempted second-degree rape.

The investigation continued. What detectives learned led Snohomish County prosecutors on Friday to dismiss the case.

“I can’t prove beyond a reasonable doubt at this time,” deputy prosecutor Robert Grant said.

Police have no reason to doubt that a crime happened. They do have questions whether Williams is responsible, court papers show.

DNA testing performed on the woman’s pants and underwear turned up some genetic material but Williams was excluded as a contributor, Grant said in court papers.

Meanwhile, detectives’ efforts to pin down Williams’ whereabouts at the time of the crime turned up reasons to wonder whether he was even on this side of the Cascade Range.

“Since Mr. Williams leads a transient lifestyle with no known associates, it was difficult to track his movements,” Grant wrote.

By checking financial records, investigators learned that 15 hours before the attack, Williams engaged in a transaction at a Chelan bank. That’s 151 miles from the location of the attempted rape.

Then, just four hours after the attack, a Washington State Patrol trooper contacted Williams along U.S. 2, on foot, outside Leavenworth. He was 103 miles from Snohomish and heading west. About 20 hours later, Williams again was contacted by law enforcement, still along U.S. 2. At that time, he was 81 miles from the attack scene.

“During that contact, Mr. Williams explained to law enforcement that he was making his way westbound and heading towards Seattle,” Grant said in court papers.

His next confirmed sighting was Monroe, about 10 miles from the attack scene. By then, more than 50 hours had elapsed since the attack.

Detectives have found no evidence that Williams has access to a working vehicle, the prosecutor wrote. Indeed, in each of the law enforcement contacts he had during the week of the attack, the man was traveling on foot and twice accepted rides from police, he added.

The police sketch of the attacker loomed large in Williams becoming a suspect.

The woman helped a sheriff’s deputy create the sketch. It was widely distributed. About four days after the attack, another deputy spotted Williams in Snohomish and thought he resembled the man in the sketch. The deputy stopped to talk and took several photographs, which were sent to detectives.

The next day, a sheriff’s deputy was called to check on a person near U.S. 2 and 88th Street SE, just outside of town. The deputy was the same one who had created the sketch of the attacker, according to court papers. He offered Williams a ride to Monroe. The man told him he’d been in Snohomish earlier but didn’t go to the area where the attack occurred.

Later, the woman reportedly picked Williams out as her attacker when shown his image among a group of photographs.

The decision to arrest was based on that identification, Grant said.

Williams’ mental health issues are severe enough that he was deemed too sick to assist with his own defense. He had been awaiting transfer to Western State Hospital for restoration treatment prior to the decision to dismiss the attempted rape charge. Before that happened, the man was evaluated for possible civil commitment but didn’t meet the criteria.

The case was dismissed without prejudice, which means it could be brought again if something changes.

At this point, the case is closed, said Shari Ireton, a spokeswoman with the Snohomish County Sheriff’s Office.

“We don’t have additional evidence to go on,” she said.

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