ST. GEORGE » Desert Hills High School administrators and a school resource officer thought a pistol they approved for use in the play "Oklahoma" was a harmless imitation until a blank discharged from the gun Saturday and killed a 15-year-old student.

Craig Hammer, the Washington County School District's executive director for secondary education, said Monday that the .38 caliber pistol that killed Tucker Thayer was offered to the school's drama instructor by the parent of a student in the play. Hammer said that the parent didn't tell authorities the gun was real.

"They always thought it was a prop gun," Hammer said.

Several hours before the play was to start, Tucker removed the gun from a locked cabinet and it somehow discharged, said St. George police Sgt. James Van Fleet. The gun was loaded with a blank that struck Tucker in the head. He died Saturday about 10 p.m.

Blank cartridges are tipped with plastic or cardboard instead of metal and contain gunpowder and primer.

"At this time, we do not know how the gun came into the possession of the student," a news release from the school district states.

Administrators and the resource officer, who is employed by the St. George Police Department, allowed the "blank gun" to be used as an off-stage sound effect, according to the news release.

The guidelines say a parent "would be responsible for its safety and use in the play," Van Fleet said.

The guidelines were put into place after an October incident at the school. That incident, coincidently, also involved Tucker, Hammer said.

Tucker had taken a wooden, nonfiring rifle home to fix it during his lunch break, Van Fleet said. When he returned to campus, police were told that a student had brought a real rifle to school. Police put the school on lockdown, investigated and confirmed the rifle was a prop for the same play, Van Fleet said. The guidelines were intended to prevent a similar scare.

Investigators have been meeting with the parent who owned the gun that shot Tucker, but are not releasing his name.

"Right now, this is still an ongoing investigation," Van Fleet said.

Police also are not saying whether the school broke the law by allowing the gun on campus.

"Everything is being looked at," Van Fleet said. "I'm not going to say yes or no."

Carol Lear, attorney for the Utah State Office of Education, noted that Utah state law punishes possession of a firearm or dangerous weapon on school grounds or around schools as Class A and Class B misdemeanors, respectively. However, there are exceptions. Chief among them is Utah state law exempting concealed weapon permit holders from the prohibitions against firearms on school campuses. Those holding permits to carry weapons may take guns onto school property, according to state law. A firearm also may be brought on campus with permission of a school administrator.

Many Utah school district policies prohibit not only firearms but any facsimile or replica of firearms on school campuses.

By coincidence, Alta High School drama students will be producing the same "Oklahoma" play for four days, beginning Nov. 20. Julie Sauve, who teaches drama at the school, said her students will be using plastic toy guns and a downloaded computer sound clip to simulate gunfire. Sauve notified school administrators and got approval to use gun replicas before rehearsals began. In addition, Sauve said she must check the toy guns out to assistant directors before they can be checked out to students. The replicas are not allowed beyond the rehearsal stage.

The toy guns and sound clip "doesn't sound great, but it works, and it's safe," Sauve said. "With guns in schools these days, I don't want to cause alarm if someone mistook it for something they didn't know about."

On Monday, the mood was somber at Desert Hills, which opened this year.

A moment of silence was held in honor of Tucker, and many students were dressed up in honor of the deceased student.

At Tucker's house on Monday, a procession of friends and neighbors stopped by to pay condolences. In the front yard, a flag flew at half staff. At its base was a memorial of balloons, a teddy bear and flowers around a picture of Tucker in his Boy Scout uniform. He was awarded his Eagle Scout badge last year.

Parker Thayer, the victim's 13-year-old brother, said Tucker was the type of person who would bend over backward to get things done.

He liked working behind the scenes of the musical production and was there every night for two months of rehearsals and during performances that had started last Wednesday.

"He was always there," said Parker. "People respected him and he respected them."

Tori Chidester, 14, who was helping Tucker on Saturday night, said she had just gone downstairs from the room Tucker was in and heard the shot go off. She said all the students involved thought the gun was approved by police and school authorities.

Nefi Olivia, a friend of Tucker's, said he was shy at first, but warmed up quickly.

"He was a cool guy," Olivia said.

Gary Chidester, a Thayer family friend, said Tucker's funeral will be at 11 a.m. Saturday at the LDS stake center on Brigham Road in St. George.

People can contribute to a fund in Tucker's name at any Wells Fargo bank,

mhavnes@sltrib.com

Tribune staff writer Ben Fulton contributed to this story.