NAMPA -- A Canyon County family is frustrated with the slow wheels of justice, seeking closure and answers after the death of a beloved husband and father.

It's been just over a year since 64-year-old John Pew was killed in a bizarre crash on Northside Boulevard in Canyon County. Twelve months later, his family doesn't have closure.

MORENampa man dead after car falls off overpass, lands on pickup

Idaho State Police say they conducted a thorough and extensive review of the case, but the Pew family is frustrated with how long the investigation and prosecution is taking. They feel there's been a lack of communication over the last year.

But Idaho State Police tells KTVB these types of extensive reviews take time in order to avoid mistakes.

"We deal with it every single day," John Pew's daughter, Misty Johnson, said. "There's not a day that goes by that we don't think about it."

Every passing day is another that leaves Pew's family feeling like they're in the dark.

"I'm just reaching and grasping for straws, trying to figure out who out there is going to help us get some answers that we need," Johnson added.

Answers about what exactly happened on that fateful day, and what is going to be done about it.

"There was a lack of communication. I was the one always having to call. They weren't calling us with updates even though we had been assigned a victim's coordinator," Johnson told KTVB.

John Pew was driving north on Northside Boulevard around 5:15 in the morning on March 29, 2016, when a car veered off the I-84 overpass right above him, landing on top of his truck and crushing him. Police say the driver of that car is Tyler Callahan of Weiser, who was 21 years old at the time of the crash. Police say there were two other passengers in his car with him at the time.

ISP investigated the crash for several months and then turned it over to the Canyon County Prosecuting Attorney's Office in November.

"This has been a terrible tragedy for the Pew family," Idaho State Police District 3 Crash Reconstructionist, Cpl. Oliver Chase, said, "We conducted an extensive investigation from the start of this collision, including a reconstruction of this crash, looking at all toxicology results, sending those out to our labs and getting results back."

"You can't charge someone without having a full investigation, otherwise you end up mischarging someone, overcharging them, undercharging them. Those types of errors occur when you do that," Cpl. Chase added.

But Johnson says there has been one delay after another for the last year. She says a warrant was issued for Callahan's arrest a couple weeks ago and he's being charged with misdemeanor vehicular manslaughter, according to the information she received.

"I feel that it shouldn't be a misdemeanor. I feel it should be a felony," Johnson added.

According to the Idaho Repository, Callahan was arraigned on the misdemeanor vehicular manslaughter charge Tuesday. He is due back in court on May 17 for a pre-trial hearing.

KTVB also found that Callahan has a criminal background: he has been charged with careless driving and drug use/possession and will be in court on Tuesday for alleged probation violation.

Police reports KTVB received from the Pew family show Callahan tested positive for Lidocaine and inconclusive for hydrocodone.

"That makes him intoxicated, it makes him impaired," Johnson said.

With the amount of time the ISP investigation took, Johnson and her family feel it was not thorough; she doesn't believe police interviewed all key witnesses.

However, ISP disagrees.

"We interviewed all the people who would have had any information regarding this crash," Cpl. Chase said. "Most of it is toxicology, some of it is the workload here, some of it is how technical the investigation is. Some of it is time getting warrants to gather certain information."

Johnson is asking Idaho State Police to re-open the investigation. As for Callahan, she feels any charge less than a felony is a slap on the hand.

"No amount of punishment is going to bring my dad back," she said. "If he gets off on this, obviously, he's going to do it again."

Police couldn't confirm whether a warrant has been issued for Callahan's arrest. KTVB filed public records requests with ISP and the Idaho Transportation Department for crash and toxicology reports.

MORE: Wife of man crushed by car from overpass files claim

The Pew family has filed a tort claim against ITD. Pew's wife, Patty, is seeking damages exceeding $50,000 related to her husband's death.

The tort claim argues that since there was no concrete barrier between the eastbound and westbound lanes of traffic on I-84, Callahan's vehicle was free to go airborne.