Suspect in grad student's slaying killed man in '81

Amos freed in 2001 after spending time in Colorado prisons

Sara Burnett, Rocky Mountain News

Published June 29, 2007 at midnight

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The man accused of killing a Colorado Geological Survey employee was convicted more than two decades ago of strangling a 69-year-old music teacher, leaving the man's body in a bathtub and stealing instruments from his ransacked home.

Robert R. Amos, who was charged with the 1981 murder in Kansas City, Kan., under the name Dennis Lee Cook, served just under 20 years of a possible life sentence for the killing as well as an assault that occurred while he was locked up in Colorado.

He was paroled in 2001.

Public records show Amos, 44, lived in the Kansas City area for several years after he was paroled, successfully completing two years of court-ordered supervision. His last address there was in 2006.

Authorities say Amos was camping in a remote area of the San Isabel National Forest in Park County when he allegedly killed Alyssa Heberton Morimoto, 24.

Heberton Morimoto's body was found late Tuesday in a shallow creek a short distance from Amos' campsite, according to the arrest affidavit. Although authorities haven't said whether she, too, was strangled, a gray-green strap was around her neck.

Police said they found drag marks leading from Amos' campsite to the Jeep that Heberton Morimoto had parked nearby, then to the spot where her body was found, partially hidden by tree branches.

Amos denied seeing Heberton Morimoto or knowing her whereabouts, the affidavit states. Once her body was discovered, he went to his tent and refused to cooperate, police said.

Screaming for help

Heberton Morimoto, a graduate student at the University of Colorado at Denver, went to the area along Forest Service Road 434 on Tuesday morning with her co-worker, Karen Houck. The two split up to map the area. Houck set out on foot, while Heberton Morimoto took the Jeep to the end of the forest road, where the women agreed to meet.

Later that morning, Heberton Morimoto called Houck on her radio and said she'd talked with "some camper" about leaving her vehicle along the road.

About 20 minutes after that call came another transmission. This time, Heberton Morimoto was yelling for help, Houck said. In the next call, Houck heard only screaming. Heberton Morimoto sounded like she was in fear for her life, Houck said.

Heberton Morimoto's GPS coordinates appeared on Houck's radio, and she used them to run to the site Heberton Morimoto had been calling from. But when she arrived, all Houck found was the Jeep, the affidavit states. The back hatch was open and Heberton Morimoto's gear was inside.

About 30 yards away was Amos' campsite. She checked the site but saw no one. About a quarter mile away, she came upon Amos, who was jogging toward the camp. Amos seemed confused, Houck told police. He said he hadn't seen Heberton Morimoto and agreed to give Houck a ride so she could report the problem.

Along the way, the pair met up with Forest Service employee Sarah Mayben. She would later tell police that Amos' shoes and the bottoms of his jeans were wet.

The Park County Sheriff's Office received a call around 1:30 p.m. from the Forest Service, according to the affidavit. Around 3 p.m., search-and-rescue crews began looking for Heberton Morimoto.

When they arrived at the site, authorities said they found a pair of wet shoes and wet jeans hanging out to dry near Amos' tent.

Amos told police he had been camping there, alone, for two or three days. He said he left his campsite around 9 that morning and didn't return or see anyone else until he came upon Houck. He also pulled some pills out of his pocket, telling officers he has Stage 3 cancer.

People who were camping nearby told officers they heard what sounded like gunshots or fireworks Tuesday morning.

When officers found Heberton Morimoto's body later that night, they also discovered a rifle and a shoe print nearby, the affidavit states. In Amos' truck, they found a sword, axes and a machete.

Amos was arrested Wednesday at the campsite. He is being held on $800,000 bail.

Served time in Colorado

The spot where Amos had been camping was just a few miles from one of the many Colorado prisons in which he served time during the 1980s and 1990s.

Amos was sent to Colorado to serve a term of 15 years to life following the 1981 murder of Albert F. Bronson. The reason he was sent to Colorado instead of serving his sentence in Kansas was unclear Thursday, Department of Corrections officials said.

Amos was 19 at the time of the murder.

According to reports from the Kansas City Star, he was arrested at his home three months after Bronson's son discovered the body. Police searching Amos' home found musical instruments missing from Bronson's house.

A 17-year-old also was charged with the murder, but it wasn't clear Thursday whether he also was sentenced to prison.

While in Colorado, Amos served time in prisons in Buena Vista, Cañon City and Pueblo. He was accused of attempted murder and arson at Buena Vista Correctional Complex, though charges were never filed.

In 1994, he was convicted of assault at the Colorado State Penitentiary. He was sentenced to two years in prison, to be served after his first sentence was complete.

Frances Breyne, spokeswoman for the Kansas Department of Corrections, said she couldn't comment on why Amos was paroled in 2001, or the conditions of his supervised release. It will take eight to 10 days to access his parole file for that information, she said.

Meanwhile, Heberton Morimoto was remembered Thursday as a warm, young woman who excelled in math and science and loved to play the cello. A 2001 graduate of the Denver Waldorf School, she married Rio Morimoto last December. She has two younger siblings.

Allyson Baker, a teacher at Waldorf, said Heberton Morimoto hoped to one day be a teacher there, following in the footsteps of her mother.

"She had tremendous hope going toward the future," Baker said.

Rap sheet

Robert R. Amos/Dennis Lee Cook criminal history:

• 1982: Convicted in Kansas City, Kan., of second-degree murder, burglary and two counts of theft. Sentenced to 15 years to life in prison. Later that year, he is sent to Centennial Correctional Facility in Cañon City. The reason for the transfer is unknown.

• 1992: Accused of attempted murder and arson for a New Year's Eve incident at the Buena Vista Correctional Complex, where he had been moved in 1987. No charges filed.

• 1994: Charged with assault while at the Colorado State Penitentiary in Cañon City, where he had been transferred in 1993. Sentenced to two years in prison, to run after the completion of his original sentence.

• November 2001: Paroled from San Carlos Correctional Facility in Pueblo, where he had been housed since 1999. Returned to Kansas for supervision.

• Feb. 13, 2004: Kansas Department of Corrections discharges him from parole.

• June 27, 2007: Accused of first-degree murder in the death of Alyssa Heberton Morimoto.Source: Colorado Department Of Corrections, Kansas Department Of Corrections.

Staff writers Rosa Ramirez, Ivan Moreno and Tillie Fong contributed to this report.

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