Having concluded that his lie to a federal grand jury impeded the investigation into the disappearance and slaying of Kiplyn Davis, a federal judge on Tuesday sentenced David Rucker Leifson to four years in federal prison.

Leifson's mother broke down in tears in court as U.S. District Judge Tena Campbell read the sentence aloud, saying there was a need to send a message that lying in the judicial process should not be tolerated.

"If there was any need for deterrence it is here," Campbell said.

Assistant U.S. attorney Carlos Esqueda said people who keep the truth from the justice system are preventing justice. "When people lie, it prevents us from investigating," he said.

Specifically, Esqueda said Leifson's lie before a federal grand jury about a heated argument he had with perjury co-defendant Timmy Brent Olsen prevented the FBI from pursuing why Leifson has refused to this day to cooperate with investigators and why Olsen's level of cooperation turned cold.

Court records show that in March 2005, Leifson was called to testify before a federal grand jury and was asked about an argument he had with Olsen regarding Davis' disappearance. Leifson denied that it was a heated argument but prosecutors say they had recorded a conversation from a person wearing a hidden wire where Leifson threatened Olsen's life and threatened to "shoot him in the head," FBI Special Agent Mike Anderson testified in court Tuesday.

In a plea agreement accepted last year, Leifson admitted to lying when he denied having two heated arguments with Olsen, furious that Olsen had told others that Leifson was behind Davis' disappearance. According to the indictment against Leifson, two people were witnesses to both confrontations, and a third witness recorded Leifson admitting to having the arguments while wearing a concealed wire.

During Olsen's perjury trial in July 2006, Olsen's former girlfriend testified that while she and Olsen were "dragging" Main Street in Spanish Fork in the summer of 1996, about a year after Davis vanished from school, an angry Leifson forced their car off the road. The woman said Leifson walked up to their car and warned Olsen to stop telling people that he was involved in Davis' disappearance and death and that he "better keep his mouth shut."

Witnesses testified that Olsen on several occasions boasted about raping and murdering Davis, only to later deny it to the federal grand jury. He was sentenced to 12 years in federal prison for perjury.

Esqueda said had Leifson been truthful about the argument, they would have been able to confront Olsen directly with specific details. Currently Olsen and co-defendant Christopher Neal Jeppson also face murder charges in state court for Davis' death.

Leifson's defense attorney, Ed Brass, said his client never denied to the grand jury of having an argument with Olsen but instead denied how heated it was.

Anderson said to this day, Leifson has refused to sit down and talk with investigators about what he knows about Davis' disappearance.

Davis vanished from Spanish Fork High School in 1995. Investigators believe she was taken up Spanish Fork Canyon, where she was raped, killed and buried in an unmarked grave.

After ruling that Leifson's lie interfered in a murder investigation, Campbell said she was also troubled with the way Leifson seems to treat women. She pointed to violent verbal threats Leifson left on the phone of an ex-girlfriend, for which he was later charged with a misdemeanor in justice court. Campbell also took note of how Leifson has mistreated several female probation officers.

When asked if he had anything to say to the court, Leifson said he had no comment.

Campbell then sentenced Leifson to serve 48 months in federal prison and ordered him taken immediately into federal custody. Leifson was also ordered to serve three years probation after he serves his sentence.

Outside of court, Davis' father said he wished people would come forward and tell the truth so everyone involved could get on with their lives.

"This is a big day," Richard Davis said. "We got another one behind bars." Davis said he grew up with Leifson's father and felt for his family, adding all of their grief could be avoided if Leifson would sit down and tell the truth.

A few weeks ago, officials in Utah County revived the search for Davis' body given new information in the case. Davis said that search has been called off when it turned out the information was bogus.

"We just want to bring her home," Richard Davis said. He said he will not rest until that is done.

E-mail: gfattah@desnews.com