A jury deliberated for about two and a half hours before convicting Tyler Aaron Gibbens, 16, of first-degree murder last Friday.

Gibbens was convicted of shooting to death Anthony Risko on the victim's 12th birthday last June 8.

Gibbens is scheduled to appear for sentencing July 16.

An additional charge of assault with a deadly weapon was dropped by the state.

The jury was polled at approximately 7:30 p.m. in Judge Robert Lane's courtroom over the sound of sobs from both mothers of the young boys involved in the tragic course of events.

The verdict concluded a four-day trial.

According to testimony by Duston Oliver, Gibbens' "best friend," who was at the Gibbens home when the shooting took place, he walked out of the kitchen to find his friend pointing the rifle at Risko's head and saying, "'This is a real gun,'" and asking Risko, "'Are you ready?'" several times before firing.

After the shooting, both Gibbens and Oliver initially attempted to claim that the shooting was accidental, going through four versions of a story in which both boys claimed Risko shot himself.

As Sheriff's Dep. Ed Howard testified, "The story continued to change."

Howard testified that he was contacted by Oliver's mother two days after the shooting and interviewed her son again, at which point the youth related the events about which he testified.

Det. Joe Close also testified during the final days of the trial, explaining to the jury how, after arriving at the house, he found a live round in the chamber of the weapon, although it did not have a magazine in it.

Later, however, Close said he searched the home and discovered a magazine holding eight live rounds underneath a shirt in the closet of the master bedroom.

He also said he checked all the other weapons in the Gibbens home after the shooting and none was loaded.

By the time closing arguments began late Friday afternoon, much of the focus was on what degree of murder Gibbens allegedly committed.

Because he was charged with open murder, he could have been deemed guilty of first- and second-degree murder as well as voluntary or involuntary manslaughter.

Deputy District Attorney Kirk Vitto argued that the shooting was intentional, emphasizing Gibbens' repeated attempts to lie to authorities.

"The story has changed and changed and stopped just short of what the evidence has shown to be the truth," Vitto added. "Perhaps because everyone knows that murder is wrong."

In response to testimony that Gibbens was badly shaken and upset immediately after the shooting, Vitto told the jurors, "It's one thing to think something in your mind, it's another to see the stark reality of your intentions. He intended to pull that trigger."

Defense attorney Tom Gibson argued that if Gibbens was guilty of anything, it was involuntary manslaughter, which he told the jury "fits like a glove" to the crime committed.

"There was no intent to kill in this case," Gibson said. "It was reckless, but it was accidental. It was mean-spirited, but it was accidental."

He emphasized that there was no evidence that Gibbens had loaded the gun prior to shooting Risko and also stressed that Gibbens "should be convicted of what he did, not of what Mr. Vitto says he did."

Gibbons stressed to the jury, "It's not deadly and dangerous if you don't know the gun is loaded."

First-degree murder is punishable by death in Nevada, although Gibbens' age at the time the crime occurred, 15, is a mitigating circumstance, and as such he cannot be given the death penalty.

The category A felony is also punishable by life imprisonment without parole, life imprisonment with parole eligibility after a minimum of 20 years, or a definite term of 50 years imprisonment with parole eligibility after 20 years.

Juveniles charged with murder Nevada are automatically tried as adults.