Best friends charged with murder -- a real-life "Thelma and Louise"?

A philandering husband is dead, leaving a mistress, his wife and her friend as possible suspects

Produced by Alec Sirken and Taigi Smith
[This story was first broadcast on Oct. 6, 2012. It was updated on April 13, 2013.]

LAKE CHARLES, La. | Robyn Davis and Carol "Sissy" Saltzman do what southern women have always done when times get tough: They head to the salon to look their best... and they are doing it together.

You won't find two women who are closer.

"It's the kind of friendship that all people should have," Robyn explained. "...it's the one person that you can call no matter what and they're there regardless... and I mean, most people don't have that..."

"She is a very generous very kind, loving person. She's a wonderful mother..." Sissy told "48 Hours." She then turned to Robyn. "You know, you are. You're a great girl, I love you."

"Well thank you, I love you too, sister..." said Robyn.

These days their 20-year friendship is more important than ever, since they've been charged with murder -- together -- after Robyn's husband was shot to death alongside his car on an isolated road. Both women adamantly deny the charge.

"It's unconscionable that they can do this to innocent people," said Sissy.

"[I] never could I have imagined this would happen to me or anybody else in America. But I've come to realize that it can happen to anybody," said Robyn during her salon visit.

There were no salons in the county jail where Robyn and Sissy spent two months before getting out on bail.

"How long were you in jail?" "48 Hours correspondent Erin Moriarty asked Robyn. "Sixty-seven days," she replied.

"They wouldn't let us see or speak to one another," Sissy told Moriarty.

"What was it like for you, Sissy?"

"Um. Well, it wasn't nice," she says with a laugh. "It was pretty tough, it was."

Added Robyn, "I cried and I cried and I cried. I cried for at least three weeks."

Robyn and Sissy are preparing for trial and the fight of their lives: To convince a jury they had nothing to do with Brian Davis' death.

Brian and Robyn Davis
Brian and Robyn Davis
Robyn Davis

She loved the man, Robyn says, although she admits that's not how the relationship started when she first met him at the office in 2001.

"I said, 'Where the hell did you all get him from?'" Robyn told Moriarty.

"Does that mean you didn't like him at first?"

"No, not at all! We did not like one another period," said Robyn.

They worked together at an insurance company in Hammond, La.

"I can remember the phone call when she first went out with him," Sissy said laughing. "She's like, 'You're not gonna believe this. ...I went out with this guy, Brian, that I work with...' And I was like, 'Yeah, call me back and let me know how that works out for you (laughs).'"

It did work out... at least for the most part. They married in 2008, after a four-year courtship.

"I was happy. I was at home and you know, he was working," Robyn said. "For the first time in my life I just worried about nothing, I mean, just nothing."

It was Brian's third marriage and Robyn's second. Combined, they had six children; Robyn had two, Brian had four.

Asked how she would describe Brian, Sissy told Moriarty, "Loud and proud, I mean...he was funny. He was a great dad too. I mean, he's a people person, you know, people person. Everywhere he went he talked to somebody about something. He knew something about everything."

To everyone who knew him, including his younger brother, Scott, Brian was a man who loved a good time.

"He always had a smile on his face. He had fun whether it was work or whether it was play. He laughed about it," said Scott.

But sometimes Brian's idea of fun got in the way of his marriages. Brian had an eye for other women... and he didn't just look.

"So he wasn't always faithful?" Moriarty asked.

"No," Robyn replied.

"He had been caught twice in Baton Rouge before they ever moved here," added Sissy.

"With another woman?" asked Moriarty.

"Yes, two different women. You know, then they moved here and...he still wanted to marry her," Sissy explained. "I said, 'Robyn, there's nothing wrong with loving Brian...He does love you. And if you choose to stay with him, you can't hold this over his head 'cause you'll never have a good marriage...Then when she finally decided she was ready to marry him, I mean, she was just...I'd never seen her happier, honest to God, never seen her happier."

But Robyn wasn't happy about the fact that Brian was still cheating on her.

Her daughter, Kelsey, who lived with her and Brian, didn't quite trust him.

"I didn't know that she knew. I always thought she was oblivious to the whole thing," Kelsey explained. "You could tell that he was up to something...he was flirtatious with women, everywhere we went."

Robyn saw it too.

"So what did you choose to do?" asked Moriarty asked Robyn.

"Suck it up and you know, put my best foot forward and rock on," she replied.

"It was very, very awkward, and I felt really bad for what I did," said Fannie Dietz, one of the women Brian was cheating with. Their two-year affair began before Brian married Robyn and continued throughout the marriage.

"Feelings developed and it just kept escalating from there," Fannie told Moriarty.

"Did you love Brian Davis?"

"Yes I did," she replied.

"And did Brian love you?"

"Yes."

The affair had ended a few months before June 29, 2009, when Brian Davis disappeared. According to Robyn and Sissy, he had left to go boat shopping and never came home. His body was discovered on a deserted road by a man out test driving a car.

Video: Witness talks about finding Davis' body

"He was shot four times in the back and he didn't have a chance. He didn't see it coming," said Calcasieu Parish Sheriff Tony Mancuso.

At the crime scene, Sheriff Mancuso says investigators uncovered several strange clues: Brian's car was jacked up, his shoes were off, his belt was undone and some of his valuables were missing.

"When you first heard that your brother had been killed, what did you think?" Moriarty asked Scott Davis.

"My first thoughts were he was looking for a boat. Someone killed him. Someone...Something went bad during a transaction," he replied.

But just hours into their murder investigation, police started to wonder if Robyn was involved based on the way she was reacting to her husband's death.

"I eventually walked over there and had a brief encounter with her to tell her just, 'Hey, I'm sorry about your husband,' you know, 'we're gonna do everything we can do to try to figure out why this happened and who did this,'" Mancuso explained, "but she was more interested and kinda joked about me knowing her friend Sissy's boyfriend."

That's when Sissy, too, came under scrutiny. Special prosecutor Rick Bryant believes the two best friends plotted Brian's death.

"So you really believe these two blonde, middle-aged women lured Brian Davis out to this secluded spot and then shot him four times, cold-bloodedly, and watched him die?" Moriarty asked Bryant.

"Absolutely...Absolutely," he replied.

To the women's many friends, including Marcy Wilson, the whole idea is preposterous.

"There is no possible way! Robyn can't even step on a roach, Sissy's barely five foot tall...neither one of them know how to use a gun," she exclaimed. "This is stuff you watch on TV...that you never imagine that it would happen to you or to someone you love..."

"But these women do not look like cold-blooded killers," Moriarty noted to Rick Bryant.

"Well, there you go! Tell me what a cold blooded killer looks like," he said. "... murderers come in all shapes and sizes."

It would take months for police to build their case and arrest the women.

"She's your best friend," Moriarty said to Sissy.

"Oh yeah," she replied.

"And Robyn says you'd do anything for her."

"Absolutely."

"Would you, if she asked you to kill somebody, would you do that?"

"Oh, my God. No, no, not for her, not for Jesus Christ himself, no, no, no," Sissy replied. "I don't have that in me."

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