Quintin P. O’Dell avoided a possible death sentence — and spared a jury a horrifically graphic criminal trial — by admitting Thursday that he used a hatchet to slay a co-worker as she fished on a day off.

He also admitted sexually assaulting another friend and disemboweling her with a razor blade.

The second victim survived her attack, which happened nearly seven months after O’Dell bludgeoned Alissa F. Shippert, 22, to death along the Platte River at the Platte Falls Conservation Area in 2011.

In exchange for guilty pleas on first-degree murder and four other counts, Platte County Prosecutor Eric Zahnd tabled plans to pursue the death penalty against O’Dell, 23.

“I would have had no hesitation in asking a jury for the death penalty, given the circumstances in this case,” Zahnd said afterward.

However, the families of both victims did not want to endure a lengthy death penalty trial and prolonged appeals, he said.

The murder count carries an automatic sentence of life in prison without parole. O’Dell also was sentenced Thursday to life for first-degree assault, 100 years each on two counts of armed criminal action and seven years for deviate sexual assault. The sentences will run consecutively.

O’Dell, who has been on medication for a bipolar disorder since being charged, killed Shippert on June 1, 2011, and slashed the abdomen of a 21-year-old Ferrelview woman on Dec. 26, 2011. Prosecutors never determined what prompted his attacks.

He apologized to the surviving victim and both families, saying, “I am sorry for what I did.”

O’Dell looked straight ahead and showed little emotion as Platte County Circuit Judge Abe Shafer announced the sentences.

Earlier in court, Landis Shippert, Alissa’s father, talked about how his daughter had planned to join a church mission trip and travel to Joplin to help with post-tornado rebuilding efforts. Alissa also had cut her long hair and saved it in a plastic bag, planning to donate it to cancer patients, he said.

“She was a wonderful person and a wonderful daughter,” Landis Shippert said. “Everyone in the community thought of her as their daughter and their sister.”

The second victim attended the sentencing but did not speak. In a statement read by her sister, the victim said she couldn’t believe that a good friend assaulted her the way O’Dell did. They had attended high school together.

O’Dell’s lawyer, Thomas J. Jacquinot, said his client agreed to the pleas to bring legal closure and avoid the death sentence.

The allegations against O’Dell shocked and enraged the Platte City community. O’Dell had become an Eagle Scout as a teenager, toiled on computers and worked at Casey’s General Store along Missouri 92 in Platte City for about two years.

He attended Alissa Shippert’s funeral and even offered his condolences, Landis Shippert said.

Alissa, who also worked at the Casey’s store, was known to go fishing on her days off.

O’Dell told investigators he happened upon her along the river the day he killed her. They talked for two hours as he watched her fish. When her line snagged, he went into the river to free it, lost his footing and went under. Alissa thought he was drowning.

When O’Dell eventually made his way back to her from downstream, she yelled and slapped him for scaring her. O’Dell struck Alissa in the back of the head with the hatchet, which he had found along the bank, Zahnd said. She fell to the ground, face up. O’Dell dropped to his knees and repeatedly struck her in the face with the hatchet until she stopped crying and breathing.

O’Dell then pulled her body into the river. Afterward, he went home and fell asleep.

Alissa’s body later was found wearing only a bikini top.

Months later, O’Dell slashed his friend’s abdomen, causing her intestines to fall out onto her living room floor. O’Dell had gone to her apartment Christmas night to hang out with the woman, whom he had known for years, Zahnd said.

The victim told detectives that she awoke the next morning and went into the bathroom, holding her abdomen because it hurt. She looked in the mirror and saw she had been cut open and was holding her intestines.

She panicked and fell into the bathtub before eventually making her way across the hall to a neighbor to get help, Zahnd said.

O’Dell had left the apartment earlier, after collecting beer bottles he had brought. When he awoke the next morning at home, he found dried blood on his hands and shirt. He threw away the shirt and beer bottles. During questioning in that assault, O’Dell also detailed to investigators how he killed Alissa Shippert, Zahnd said.

“Miraculously, our second victim survived and her ability to identify her attacker was extraordinarily helpful in this case,” Zahnd said. “Alissa Shippert was a vibrant young woman whose life was tragically cut short by this man and his evil acts. I believe the world is going to be a better place with Quintin O’Dell behind bars until he breathes his last breath.”

To reach Glenn E. Rice, call 816-234-4341 or send email to grice@kcstar.com.