An 8th District Court jury deliberated for less than three hours before finding Saenz guilty on all counts, according to court officials.
On April 11, 2013, Olsen was found shot to death near Fort Duchesne on the Uintah and Ouray Indian Reservation. His 2011 Mazda 3S was gone.
Nearly two weeks later, police found Olsen's car Saenz was driving it in Arizona. Officials arrested him in Arizona and he was brought back to Utah to face charges.
Saenz and Olsen, who was a convicted sex offender, were believed to be in the Uintah CountyJail at the same time at one point, but they did not share a cell, according to Uintah County Undersheriff John Laursen.
At the time of the slaying, Saenz was out on bail on an unrelated sex abuse charge and had an ankle monitor. He cut the ankle monitor in Roosevelt on the day of Olsen's death, according to police.
The prosecutor and defense attorney could not be reached Friday for comment.
In the sex abuse case, Saenz was accused of following a woman home on a shuttle bus from a nightclub early June 10, 2012, according to the charges. Once they got off the bus, he punched her twice and dragged her across a street to a spot outside an apartment complex, where he raped her and broke her cellphone, charges state.
Saenz pleaded guilty last June to first-degree felony aggravated sexual assault. He was sentenced to serve a term of 15 years to life in the Utah State Prison last August.