CALDWELL -- A Weiser man will spend at least 87 days in jail after his car plunged off a Nampa overpass last year, killing another driver on the street below.

Tyler Callahan was sentenced Tuesday to a year in jail for misdemeanor vehicular manslaughter. But Judge Debra Orr told Callahan she planned to review the sentence - and may choose to place him on probation instead - at a post-sentencing hearing Sept. 8.

Callahan, then 21, was headed west on I-84 March 29, 2016 when he lost control of his car and veered through the median and over the edge of the overpass. His Chevy Impala smashed down onto a pickup truck on Northside Boulevard, killing 64-year-old John Pew of Nampa.

At his sentencing hearing, Callahan told Orr he had drifted off at the wheel just before his car's deadly drop.

"I fell asleep, lost control of the vehicle," he said. "I woke up and all I could see was broken glass and blood in front of me.”

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He pleaded guilty to misdemeanor vehicular manslaughter in Pew's death Thursday.

Pew's family has argued Callahan should have faced a heavier charge, and maintained their suspicions that his driving was impaired by something more nefarious than lack of sleep when the wreck happened.

But that belief is not backed up by any evidence in the case, Judge Orr said.

“There is no indication that Mr. Callahan was driving the vehicle under the influence of drugs and alcohol,” she said.

The investigation into the wreck took more than a year. According to Idaho State Police, Callahan's blood tested negative for alcohol, positive for the topical anesthetic Lidocaine and inconclusive for hydrocodone. Both drugs were administered by paramedics and hospital personnel after the crash to treat Callahan's injuries, prosecutors confirmed.

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Prosecutor Kimberlee Bratcher said two teenage passengers in Callahan's car had been huffing cans of Dust-Off before the wreck. Callahan's blood was tested for fluorinated hydrocarbons, which would indicate the presence of so-called "volatile inhalants," and would have revealed whether or not Callahan had also been using the canned air to get high before the crash.

The test came back negative.

Bratcher noted that inhalants typically clear quickly from the bloodstream, but stressed that the prosecution did not have any evidence that Callahan had used the canned air or any other drug.

That wasn't good enough for Pew's family members, whose letters to the judge were read aloud in court.

Misty Johnson, the victim's daughter, wrote she did not believe Callahan's claim of falling asleep behind the wheel.

“This was your choice, your actions, your decision that led you to be here,” Johnson wrote, asking for "a heavy hand" from the courts.

Johnson wrote she was incensed by an email from Callahan in which he wrote that her father "was in a better place" and complained about his own injuries. She still had to regularly drive through the intersection where her father died, Johnson wrote, and found herself wondering about the difference a few seconds could have made.

“Maybe if he was a faster driver, maybe if the light hadn’t turned green,” Pew would still be alive, Johnson told the judge.

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Patty Pew, John's wife, wrote that his death had left her and the rest of the family bereft, and reminisced about the last time he kissed her and told her he loved her as he headed out the door to go to work the morning of the crash.

She echoed Johnson's sentiment that a misdemeanor was too light a charge for the severity of her loss.

“You, Tyler, need to stand up and be a man," she wrote, addressing Callahan. "You know what happened, and how it happened.”

A slideshow of Pew's life played before the sentence was handed down, prompting tears from relatives in the gallery. Photos showed the victim as a young man, at weddings and family gatherings, and posing with his children and grandchildren.

“He had decades left," Bratcher told the judge. "Now he’ll be missing births, he’ll be missing weddings."

The prosecution asked for a year behind bars, pointing to Callahan's criminal history - including drug and alcohol convictions, inattentive driving, reckless driving and speeding tickets - as well as previous failed attempts at probation.

Defense attorney Jonathan McCabe argued a year in jail was too severe a penalty, noting that Callahan had immediately taken responsibility for his role in the collision.

“Mr. Callahan has to live with what happened here,” he said. “This was an act of simple negligence."

Orr seemed to agree.

The judge ordered Callahan to be immediately taken into custody to begin serving out the yearlong jail sentence, but hinted that the Sept. 8 review hearing could bring a change.

Orr instructed both Callahan and Pew's family to think about ways that Callahan's sentence could pay tribute to the life that was lost, like time spent cleaning up Pew's memorial, or volunteering at a cause in the community.

She added that she would consider their suggestions at the hearing, rather than committing to have Callahan serve out the entire sentence.

“I don’t think that honors John Pew,” Orr said of a year in jail.

In addition to the jail time, Callahan's driver's license will be suspended for three years. Restitution in the case will also be decided at the Sept. 8 hearing.