Detectives revealed how DNA from a plastic cup of coke led to the conviction this year of a man for the rape and murder of an 18-year-old jogger 30 years ago.
Amanda ‘Mandy’ Stavik vanished just before 2pm on November 24, 1989, while jogging with her dog near her home east of Bellingham, in Washington State.
Three days later, a volunteer firefighter came upon the missing teen’s lifeless, naked body in the South Fork of the Nooksack River.
Her neighbor, Timothy Bass, 51, was found guilty of her rape and murder in July this year and was sentenced to nearly 27 years in prison.
Detectives claimed it was new DNA evidence – namely Coke from a plastic cup that Bass drank from – that led to Bass’ arrest over her murder in December 2017.
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Timothy Bass (left), 51, of Washington state, was convicted on charges of murder rape and kidnapping in November 1989 death of 18-year-old Mandy Stavik (right) in July this year
A new ’20/20′ special on the rape and murder of Amanda ‘Mandy’ Stavik features interviews with her mother Mary, (pictured), who spoke of the moment she realized she was missing
A two-hour ’20/20′ special, due to air on September 20 at 9pm ET on ABC, details how police finally arrested Bass and features police interview footage of the moment he claimed he had ‘slept’ with Stavik.
A 1989 graduate of Mount Baker High, Stavik was home on break from her freshman year at Central Washington University.
When her German shepherd, Kyra, returned home alone three hours later, a search for the 18-year-old woman began.
Three days later, a volunteer firefighter came upon the missing teen’s lifeless, naked body in the South Fork of the Nooksack River.
The 20/20 special features interviews with Mandy’s mother, Mary Stavik, Bass’ ex-wife Gina and Kim Wagner, Bass’ co-worker who helped break the case.
Mandy’s former boyfriend, Rick Zender, Bill Elfo, Whatcom County sheriff, and Kevin Bowhay, lead detective on the case, also give their insights on the horrific crime.
Her mother Mary told of the moment she realized something was wrong, saying: ‘She went with her dog Kyra, she had been gone longer than usual for her run.
‘When she didn’t come back, when she should’ve come back and then the dog came back without her, I was panicky, the first person I called was her boyfriend.
‘I don’t think I ever believed, ever, that they would catch the guy.’
In 2009 Detective Bowhay began investigating the case and performed a DNA sweep of the town, requesting samples from dozens of men who lived in the area in 1989, but no matches surfaced.
Footage shown in the documentary of Bass being interviewed over the murder sees him throwing his hands up in the air and saying, ‘Ah to hell with it, I cant do this, I cant. I slept with her’
Timonthy Bass quickly married and moved out of the area following Mandy’s death. When detectives first approached Bass in 2013 he refused to hand over his DNA for testing
Soon Bowhay focused on Bass, who lived on the same street as Mandy at the time of the murder.
Bass quickly married and moved out of the area following Mandy’s death. When detectives first approached Bass in 2013 he refused to hand over his DNA for testing.
After Bowhay visited Bass’ workplace, his co-worker Kim Wagner figured out authorities were interested in Bass.
She collected Bass’ used plastic water cup from the garbage and turned it over to police for testing.
Bass’ DNA was retrieved from the cup and was matched the DNA taken from Mandy’s body and police arrested him in December 2017. This July, Bass received 320 months in prison for the first-degree murder of Mandy.
Boway said: ‘You were very aware of this horrific crime of a young girl that was brutally abducted.’
The 20/20 special features an interview Rick Zender, Mandy’s former boyfriend. They are pictured here together in an undated photo
Friends also told of the moment they realized Tim Bass was arrested over the murder in 2017
‘I think when he realized, once we did have his DNA, then he switched.’
Footage shown in the documentary of Bass being interviewed over the murder sees him throwing his hands up in the air and saying, ‘Ah to hell with it, I cant do this, I cant. I slept with her.’
But friends revealed that they knew he was lying, as Bass would have been older than the girl.
One friend says during the program: ‘We all kind of knew that was BS, she was way way way out of his league to put it bluntly.
‘Tim’s biggest fear was that someone would show up on his doorstep with a badge and ask what happened to Mandy.
‘That it would happen like this I never would have guessed.’
Her boyfriend also reveals: ‘Mary was worried that Mandy was missing , then I got worried.’
Friends also told of the moment they realized Tim Bass was arrested over the murder in 2017, with one telling the show: ‘It could have bee anyone and everywhere we went, could have been the person that did this to Mandy.
Friends from the neighborhood revealed their shock when they discovered Timothy Bass was arrested
One friend claimed Timothy Bass’ biggest fear was that cops would come knocking at his door
‘I was like oh my god, this light went off in my head, I think I figured out who killed Mandy Stavik. He was a loner, he was quiet , he was a little bit of an oddball.’
Another friend claimed: ‘Tim’s biggest fear was that someone would show up on his doorstep with a badge and ask what happened to Mandy.
‘That it would happen like this I never would have guessed.’
At the time of her death, Stavik was a first-year student at Central Washington University and well-known in the east Whatcom County community.
She had graduated earlier in the year from Mount Baker High School, where she was an honors student, played basketball and softball, ran cross-country and track and was in the school band.
‘I think this about the biggest case ever in Whatcom County,’ Whatcom County Sheriff Bill Elfo said at a press conference announcing Bass’ arrest in December 2017.
He added that detectives had ‘doggedly’ followed hundreds of leads and looked into scores of potential suspects all across the US, and even abroad.
Stavik had graduated earlier in the year from Mount Baker High School, where she was an honors student, played basketball and softball, ran cross-country and track
The cause of Stavik’s death was listed as not inconsistent with drowning. Authorities said she may have been alive when she was dumped in the river
The cause of Stavik’s death was listed as not inconsistent with drowning. Authorities said she may have been alive when she was dumped in the river.
She had a blood clot on the back of her head, suggesting that she had been struck, and possibly knocked unconscious, according to reporting by The Bellingham Herald.
Elfo said at the time of the murder, then-22-year-old Bass was a neighbor of Stavik’s on Strand Road.
‘She would have celebrated her 46th birthday this year,’ stated Sheriff Elfo when Bass was initially arrested in 2017.
‘Her brutal murder rocked the community and she is still well remembered by many. We hope that this arrest will help bring closure to Mandy’s family and the community.’
‘Deputies forwarded DNA samples from Mr. Bass to the Washington State Patrol Crime Laboratory who reported that this DNA matched DNA recovered from Mandy’s body in 1989,’ Elfo said.
According to a statement from the Sheriff’s Office, the Laboratory determined that the match probability was 1 in 11 quadrillion.
Bass has no criminal history in Washington state, but in August 2010 his wife filed for a domestic violence protection.
According to court records obtained by The Herald, Bass’ wife claimed that her husband, with whom she has three children, watched TV shows about cold-case murders, and in one instance told her: ‘I wouldn’t get caught because I’m not that stupid. It would be easy to get away with it.’