A murder, two trials and a supportive family

The Mark and Karen Duenas story from beginning to end and why a family hopes it's not over

The Murder

Cottonwood is known for its beautiful countryside, quaint, small-town charm, and family atmosphere. On May 4, 2012 Robinson Glen Drive appeared to be just another quiet street in this rustic town with nice homes and families. But on May 5, 2012 life on the street changed.

The road accustomed to bicycles and basketball hoops was suddenly filled with ambulances, deputy patrol cars and undercover detective units.

The blue, one-story, home at the end of the street, was now the scene of a grisly homicide. Crime scene tape was wrapped around the trees in the front yard. When daylight broke, those who hadn't already been roused in the neighborhood by all the commotion began asking questions. But so early in the investigation, law enforcement had little answers.

By the end of the day detectives told local media it was a homicide case. A woman had been killed in her home. That woman was 51-year-old Karen Duenas.

She lived in the home with her husband, Mark, and their son Casey. Mark and Karen had five sons; they had lived in Cottonwood for years and were a large presence in the community. The couple's son Jason and his family lived next door.

But Karen was more than just a wife, mother, and grandmother. She was also an instructor at Shasta College and had recently become a nursing student at the college too.

On that early May morning she was found stabbed to death in her bedroom, once in the chest and twice in the back. Detectives said when they arrived to the home Karen was propped on pillows lying in a pool of blood. A bloodied blanket at her feet, her face and hands, however, had been wiped clean from blood. Karen slept alone in her room, her husband slept down the hall in a different room. The couple had slept separately for years because of Mark's strange work schedule with UPS.

The morning of the murder Mark told investigators he awoke to what sounded like cats fighting. He got up and looked around; when he didn't notice anything he walked to Karen's room. That's when he discovered his wife face down in blood. He said he heard a fluttering and gurgling sound coming from her chest. Mark said he immediately went to wake his son Casey and told him to go next door and get help from his firefighter in training brother, Jason. As Casey went next door, Mark called 911. He told the dispatcher he needed help and that there was blood everywhere. Shortly after the call, Shasta County Sheriff's deputy Troy McCoy arrived on scene. Once he determined the home was safe he allowed paramedics inside who determined Karen was dead.

From that moment on the family of Karen and Mark Duenas would never be the same. They had just lost their mother and matriarch of the family. Now, more than ever, they would have to stick together to get through this difficult time.

The Investigation

The day Karen was found stabbed to death no one was arrested for the murder. Days after the incident investigators slowly began to release more information about what happened. They also asked for the public's help. They were looking for any tips, any leads to who could've killed Karen Duenas.

Divers from the Sheriff's Department searched the ACID canal which was a few blocks from the home. Members of the Search and Rescue team combed the neighborhood.

Investigators would never say what they were searching for but just days after the murder they said they hadn't found anything. People in the neighborhood, the community, even the county began talking amongst themselves, forming their own opinions into what happened.

Was there a crazed serial killer on the lose?

Should the public be worried?

According to a Sheriff's detectives the answer was no.

"I urge the public to have trust in the Sheriff's Office. I mean I have family and friends that live in this neighborhood as well and based upon our original statement the public in general is not at risk our office still stands by that."

Several days went by following the detective's reassurance.

11 days after she was found stabbed to death in her home, Karen's husband Mark, was named a person of interest. Then, months go by where seemingly nothing happened. Mark continued to live at his home with his son but behind the scenes there was a flurry of activity with detectives and criminalists pouring over evidence.

On July 19, 2012, three months after the murder, lead detective Logan Stonehouse provided an explanation for the lack of public information. "What you see on TV the results you get back in a day. That's just not how it is out here in the real world it takes a long time for these results to come back, for the DNA process to come back. It takes weeks, if not months, if not years."

And then the waiting ended, exactly five months after the murder. On Oct. 5, 2012, Mark Duenas was arrested at his home in Cottonwood for Karen's murder. Shortly after the arrest the Shasta County Sheriff's Office released details about their investigation and why they believed Mark was guilty.

Investigators said Mark told them at one point he was in a phone relationship with another woman, named Annette Green. She lived in Idaho but grew up in Shasta County. The two knew each other in high school but never dated. They reconnected through one of Mark's coworkers on Facebook and began texting and occasionally talking on the phone.

When Karen found out about the relationship she was hurt and asked Mark to stop talking to Green. However, he bought a track phone and continued to speak to Green. Green told investigators Mark at one point had told her, "Something bad would have to happen for us to be together."

Investigators said Mark had staged a phony break-in to the home the night of Karen's murder. However he made mistakes in his efforts. They said there were no signs anyone else had been in the room. Dust on the window sill was untouched and there was furniture blocking the window where a person could potentially exit. They also said the plants under the window were unharmed. Nothing was missing from the room to indicate it was a robbery.

Karen suffered three stab wounds. One large gash to her chest and two to her back.

Investigators said there were no signs of a sexual assault.

Investigators said another sticking point in Mark's guilt was the 911 call he made in the moments after discovering his wife. They claim he said, "I found my wife shit, blood everywhere." They described Mark's behavior as strange in the hours after her body had been discovered and when deputies began securing and searching the home. They said he lay on the couch with a blanket covering his face, seemed to be sleeping and asked the deputies if they had found anything outside.

On Feb. 19, 2013 the family spoke about the case for the first time outside the Shasta County Courthouse, saying they supported Mark.

Some 20 family members from Mark and Karen's family came to support him at a trial readiness conference.

Her family standing behind her, Karen's older sister Jennifer Regelin spoke to the media, "The Tenney family would like to say they continue to give love and support to Mark Duenas, his five boys and their families."

A separate statement was also released by Mark and Karen's son speaking out against how their father has been portrayed.

They said the belief that the couple's marriage was crumbling because of an out-of-state phone relationship was false.

Mark's attorney, Ron Powell, read the statement on their behalf.

"We were aware of this relationship, including our mother, while she was not thrilled about it our parents were still very much in love."

"Our dad is a caring loving man that was deeply in love with our mother and misses her everyday just as we all do."

A Hung Jury

Opening statements for Mark's trial began on July 11, 2013. After two days of jury selection, a jury consisting of seven women and five men were seated. Shasta County Deputy District Attorney Eamon Fitzgerald represented the people, while Mark was represented by Ron Powell, from Rancho Cucamonga in Southern California. On the first day of trial, the other woman, Annette Green testified about her relationship with Mark, this was the first time the two had seen each other in person since the seventies.

She said they began talking in 2011. At first they caught up on life but eventually they began expressing feelings for each other. The two never saw each other or had a physical relationship. After a few months she told Mark she was beginning to feel guilty and they stopped talking.

Mark contacted her a few months before Karen's murder to tell her happy birthday.
In a cross examination, Powell reminded the jury that the relationship had never been physical, that the two often talked about their families, that Mark had told Annette he loved Karen, at one point saying, "He would need to be a better husband."

Several deputies who helped secure the Duenas home the night of the murder were called to the stand. They detailed to the jury what they saw when they arrived at the scene of the crime and their roles in securing the home.

Mark and Karen's son, Casey Duenas, who still lived with his parents, described what he saw the night of the murder. Casey, a baseball player at West Valley High School said both of his parents attended his double-header baseball game earlier in the day.

That was the last time the couple was seen in public together. He said nothing seemed out of the ordinary and after the game he decided to go to the movies with friends. He said when his friend dropped him off at home the light to his mom's room was off so he decided not to tell her he was home. He quickly fell asleep and shortly later was roused by his father frantically telling him to get up and go get his brother that something had happened to his mom.

Scared, Casey threw on clothes and did what his father asked. Brother, Jason, a volunteer firefighter who lived next-door said he heard footsteps on the stairs and his work pager going off at the same time. When Casey told him his parents needed help Jason ran next-door and arrived to find his mother covered in blood.

When it was his turn to make a case, defense attorney Powell was quick to point out that a speeding car was seen leaving the neighborhood that night and tracks were found around the home. Earlier in the trial the prosecution called several people who live in the area to the stand who claimed they heard a scream the night of Karen's murder, however, Powell called the Duenas' next-door neighbor, Crystal Jackson, who said she never heard a scream.

Jackson testified that she had spoken to the couple prior to the murder as they did yard work. She said they appeared happy and talked about a plan to get some debt paid off and even had a bucket list.

Powell said the prosecution treated the case like a puzzle, picking and choosing pieces they wanted to fit, singling Mark out from the beginning. He used the example of an investigating deputy telling the public there was nothing to worry about following the days of the murder. He said Mark had been fully cooperative with the investigation and wanted to help investigators.

The trial initially expected to last weeks ended up only lasting six days. The jury debated for almost three of them. On the third day they told Judge Bradley Boeckman they did not believe they would be able to come to a conclusive agreement. However, Boeckman sent them back to discuss more. By the time they were finished the jury said they were hopelessly deadlocked nine to three in favor of acquittal.

Boeckman declared and mistrial.

Mark and Karen's family who had filled the courtroom everyday were devastated at the outcome. Shortly after a mistrial was declared they tearfully gathered in the hallway to address media.

"This family is close, both sides. Always have been and we're in support and we don't see any reason not to be. It's not over, we're going to continue to fight through this, we'll stay together and try to get to where this needs to be," said Karen's brother, Joe Tenney.

"This is belief in this human being. This is not question in our hearts," declared Mark's older sister Teri Ortiz as she fought back tears.

The prosecution said they did not have a comment after the ruling because it was an ongoing case.

Take Two

The second trial began about two months later on Oct. 1, 2013.

This time there was a new prosecutor for the people. Deputy DA Stephanie Bridgett would handle the case and on the few times the court met before the second trial she said she planned to call more witnesses and anticipated it lasting longer. Jury selection also lasted longer due to the amount of attention the case had been given. Bridgett went over the same points told in the first trial, but she presented more pieces of evidence.

A knife from the Duenas' was shown to the jury that was never seen in the first trial. Experts testified it could or could not have been the murder weapon. Experts also testified blood would be easy to wash off a knife because of its non-porous surface. The screen that the prosecution claimed had been cut was also brought in and shown to the jury. When jurors listened to the infamous 911 call, Bridgett had each juror listen to the first 13 seconds with headphones.

Many family members of the Duenas and Tenney families were also subpoenaed. The defense continued to maintain that Mark had been singled out from the beginning and that law enforcement had failed to look into other suspects. That suspicious car in the neighborhood the night of the murder and tracks found around the home were overlooked.

He argued that Mark's relationship with another woman was nothing but innocent. Finally after nearly a month the attorneys rested their cases.

After a day and a half of deliberations the jury came back late Friday afternoon, Nov. 1 and said they had a verdict.


As the verdict was read Mark Duenas stared straight ahead as the dozens of family members that filled the gallery broke down in tears. As he was being led away by bailiffs back to jail Mark maintained his innocence telling several investigators sitting in the front row, "I didn't do it."

After the verdict was handed down, Mark's attorney Ron Powell, reacted, "Retrials are hard, the people have every argument you've made, every question that you've asked they have the benefit of that going in."

The DA told a different story.

"I read it fresh from the beginning and just presented it my way."

Bridgett said she believed blood found on the clothes, not visible to the naked eye was one of the most damaging pieces of evidence. "His clothing and the fact that no one saw visible blood on the clothing but after extensive work was done by the Department of Justice it became obvious there was blood all over those clothes," she said.

"It's been a long time waiting for this to happen for Karen and I think that there was justice today."

On Dec. 6 Mark was sentenced to 25 years to life in prison.

Several members of Mark and Karen's family spoke in his support, including Mark himself, against the advice of his attorney and the judge.

He said, "I never thought I would be blamed for this. Never in a million years and this is how it turned out."

Mark's attorney, Ron Powell, filed an appeal.

Outside the courtroom Bridgett responded to Mark's comments.

"I think it's very sad that he's going to make that type of statement. It just continues to manipulate the family into believing that he didn't commit this crime, that we know that he committed, that there's overwhelming evidence that he committed, and that the jury found that he committed. It's just sad that his family has to go the rest of their life feeling that they were wronged."

A Family United

Throughout the trial Mark and Karen's family has been supportive of Mark's innocence.

Shortly after his sentencing with time to rest, the family reflected on the whole ordeal.

"There's just a lot left out," said Karen's niece Keri Smith.

"And it's hurtful; it's hurtful to make these quick judgments. There's more than one person damaged by this thing. All his sons, all his family and we're people too," said Mark's older sister Teri Ortiz.

It was Christmas Eve when the two women talked about what the family has gone through over the past year and a half.

They said they were trying to be strong around the holidays because that's what Mark would've wanted.

Not long before then, Karen's brother, Joe Tenney also discussed his disappointment with how the investigation and case were handled.

"Having more information than the jury would ever have -- they didn't get it right," said Tenney.

The family said it's important their voices are heard.

"We'll do anything to let people believe the truth, and the truth is, we believe thoroughly in Mark," Ortiz strongly stated.

Tenney was close with Mark as well.

"You know you refer to him as a brother in-law but to me, we're family, we're brothers."

The family discussed the heartbreak that has come with losing Karen, and then, effectively, losing Mark.

"Things will never be the same," said Tenney.

However with the family's heavy heart, comes frustration that's been brewing practically since the day of the murder.

Mark's attorney, Ron Powell, argued in court the investigation was treated like a puzzle, with authorities picking and choosing each piece in the investigation they wanted to fit.

Tenney agrees.

"There were just a lot of little pieces that were missing or lacking in the case."

He talked about the fact Mark was a person of interest for five months before he was arrested, all the while a free man while law enforcement ensured the public they were safe.

"If they thought that Mark was the guy -- you're talking about a murderer here -- in what way does that make the neighbors or the rest of the public safe?" questioned Tenney.

There has also been criticism of Mark's behavior following the murder, the prosecution calling it strange, almost nonchalant.

According to those close to him, those claims are completely false.

"As far as reports of no remorse, no tears, we saw the tears, we saw the remorse, we saw the constant physical shake," said Ortiz.

"All the time," said Smith.

The family also said Mark was a victim of the system, saying he fully cooperated with law enforcement, answering their questions during interrogations because he wanted to help find Karen's murderer.

"He had hope. He had hope that this would all come to a conclusion at least in that part. He would also break down suddenly and cry because she was gone," explained Ortiz.

As far as the overwhelming evidence the prosecution claims they have against Mark the family said there are explanations for that as well.

They say in the 911 call it is obvious Mark is distressed and confused, getting things like his wife's age and their address wrong.

The family also says at one point a recording of the 911 call where Mark denies it is him is because the recording investigators played for him really wasn't him.

"If I had a conversation with my brother it was about dummies who did something like that, I mean how can they think they would get away with something like that?" questioned Ortiz.

Without batting an eye, without thinking twice the family said they believe the real killer is still out there.

"Absolutely. I know that none of us want to believe that it could be someone random and maybe it isn't someone random. Maybe we haven't put together the dots but random happens," said Ortiz.

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