Prosecutor Reveals ‘One Mistake’ Jodi Arias Made In The Murder Of Travis Alexander

For the first time, prosecutor Juan Martinez is revealing behind-the-scenes details from the Jodi Arias murder trial.

In a new interview with Dr. Phil, Martinez – author of Conviction: The Untold Story of Putting Jodi Arias Behind Bars – says three five-gallon gas cans helped him prove Jodi Arias had planned to kill ex-boyfriend Travis Alexander.

“She was on a short list of one,” Martinez explains of his early suspicions of Arias in the investigation. “From the very beginning when I went to the scene, I was talking to the detective and he said, ‘Well we really don’t have any suspects, but everybody keeps talking about this ex-girlfriend Jodi Arias.’

“Everyone that was there that talked about her had nothing but negative things to say about how she wouldn’t leave this guy alone,” Martinez adds.

After initially denying being involved in the death of Alexander – who was stabbed 27 times, had his throat slit and was shot in the head inside his Mesa, Arizona home in 2008 – Arias changed her story and admitted that she killed him, but claimed it was an act of self-defense.

However, Martinez says inconsistencies began to surface in her story and, soon, the evidence began to contradict Arias’ claim. Of note, Martinez says he learned that Arias had borrowed two gas cans a month before travelling to Arizona, where she eventually killed Alexander.

“With that information, I started to take a look at some of the receipts that were taken during an execution of a search warrant on her house and I saw there was a receipt for a five-gallon gas can. So now I knew that I had three five-gallon gas cans – [a total of] 15 gallons,” Martinez explains.

“And I also knew that in an interview with the police, her mother said, ‘Jodi told me that she wasn’t anywhere in Mesa and she had the receipts to prove it.’ So it was clear she was planning to keep certain receipts, but she was also planning not to stop in Arizona for gas because the 15 gallons allowed her to go through the state of Arizona without stopping for gas.”

In the end, Martinez claims it was the gas cans which helped prove the act was planned ahead of time and ultimately pre-mediated.

“Even in opening statements, the defense attorney indicated it was a trip she hadn’t planned … but the gas cans spoke otherwise,” Martinez concludes, also pointing out that Arias changed her hair color before leaving for Arizona and removed the license plates from her rental car once she arrived in Mesa. “She went to great lengths to make sure that no one could tell she was there. And, by in large, she was successful. Except for that one mistake, she probably would’ve gotten away with it.”

Martinez shares more revelations from inside the Jodi Arias trial on Monday’s Dr. Phil. Plus, hear from a juror in the case. Check here to see where you can watch.

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Foreplay

"He refused to kiss me because he said it was gross ... maybe because I had been performing oral sex, but he kissed me on the cheek and then left," Arias said in court about a September 2006 sexual liaison with Alexander.
"He refused to kiss me because he said it was gross ... maybe because I had been performing oral sex, but he kissed me on the cheek and then left," Arias said in court about a September 2006 sexual liaison with Alexander.

Foreplay

"Sometimes it hurt if it got in my eyes," Arias said on March 4, 2013, about receiving facials. "I couldn't help feeling I was kind of like a prostitute."
"Sometimes it hurt if it got in my eyes," Arias said on March 4, 2013, about receiving facials. "I couldn't help feeling I was kind of like a prostitute."

Foreplay

"Oh my God that is so debasing, but I like it," Arias said in a 2008 recorded conversation with Alexander when he said he wanted to tie her to a tree and have anal sex with her.
"Oh my God that is so debasing, but I like it," Arias said in a 2008 recorded conversation with Alexander when he said he wanted to tie her to a tree and have anal sex with her.

Sex

"To me sex is sex, there are just different ways to have sex. And it seemed like Travis was, kind of — I don't know how to put it, but it seemed like he had the Bill Clinton version, whereas over here it seemed like oral and anal were also sex to me. But not for him," Arias testified on Feb. 6, 2013.
"To me sex is sex, there are just different ways to have sex. And it seemed like Travis was, kind of — I don't know how to put it, but it seemed like he had the Bill Clinton version, whereas over here it seemed like oral and anal were also sex to me. But not for him," Arias testified on Feb. 6, 2013.

The Love Affair

"I felt an attraction to him and the feeling was mutual and I wanted to, I just wanted to, I don't know. I wanted to do what he wanted to do," Arias said of giving Alexander oral sex in September 2006, in the weeks following their initial meeting in Nevada.
"I felt an attraction to him and the feeling was mutual and I wanted to, I just wanted to, I don't know. I wanted to do what he wanted to do," Arias said of giving Alexander oral sex in September 2006, in the weeks following their initial meeting in Nevada.

The Love Affair

"I wanted to [abide] with the law of chastity because I believed that our relationship would be blessed if we did that," Arias testified.in February 2013.
"I wanted to [abide] with the law of chastity because I believed that our relationship would be blessed if we did that," Arias testified.in February 2013.

Fairy Tales

"We dated for like five months and we broke up and actually did not see each other for quite a bit,"€ Arias said. <br /><br />"€œ[We] tried to remain friends, more like buddies. We were intimate but I would not say romantic as far as a relationship goes," Arias told police on June 10, 2008.
"We dated for like five months and we broke up and actually did not see each other for quite a bit,"€ Arias said.

"€œ[We] tried to remain friends, more like buddies. We were intimate but I would not say romantic as far as a relationship goes," Arias told police on June 10, 2008.

The Love Affair

&ldquo;I believe he had aspects of himself that are beautiful and ugly, just as I do," Arias said.on Feb. 26, 2013. <br /><br /><i>Note: The domain JFineart.com was previously owned by Jodi Arias. The domain now belongs to a new owner, who has no connection to this photograph.</i>
“I believe he had aspects of himself that are beautiful and ugly, just as I do," Arias said.on Feb. 26, 2013.

Note: The domain JFineart.com was previously owned by Jodi Arias. The domain now belongs to a new owner, who has no connection to this photograph.

Fairy Tales

"When we broke up ... it was kind of a mutual thing, but I sort of more broke up with him and it was kind of hard to do because I really loved him. But, I just realized that without trust, you can`t have anything, and I had violated his trust," Arias told police on July 15, 2008.
"When we broke up ... it was kind of a mutual thing, but I sort of more broke up with him and it was kind of hard to do because I really loved him. But, I just realized that without trust, you can`t have anything, and I had violated his trust," Arias told police on July 15, 2008.

Fairy Tales

"It`s not that I don`t love Travis and it`s not that I don`t still love him, but I really needed to move on," Arias told police on July 15, 2008.
"It`s not that I don`t love Travis and it`s not that I don`t still love him, but I really needed to move on," Arias told police on July 15, 2008.

Sex

"I probably would have let him continue, but it was too painful," Arias testified in reference to having anal sex with Alexander on Nov. 26, 2008 — the day he baptized Arias into the Mormon faith. She added, "[I felt like] a piece of toilet paper."
"I probably would have let him continue, but it was too painful," Arias testified in reference to having anal sex with Alexander on Nov. 26, 2008 — the day he baptized Arias into the Mormon faith. She added, "[I felt like] a piece of toilet paper."

Sex

"I asked him to stop because he hadn't shaved and it was scratchy," Arias said on Feb, 19, 2013, in regard to Alexander allegedly performing oral sex on her the day he was killed.
"I asked him to stop because he hadn't shaved and it was scratchy," Arias said on Feb, 19, 2013, in regard to Alexander allegedly performing oral sex on her the day he was killed.

Lies

"Lying isn't typically something I just do. The lies I've told in this case can be tied directly back to either protecting Travis' reputation or my involvement in his death ... because I was very ashamed," Arias said in court on March 7, 2013.
"Lying isn't typically something I just do. The lies I've told in this case can be tied directly back to either protecting Travis' reputation or my involvement in his death ... because I was very ashamed," Arias said in court on March 7, 2013.

Lies

"If I go to trial for this and if I`m convicted for this, whoever did this is going to be sitting very pretty somewhere -- glad that it was not them," Arias told police on July 15, 2008.
"If I go to trial for this and if I`m convicted for this, whoever did this is going to be sitting very pretty somewhere -- glad that it was not them," Arias told police on July 15, 2008.

Lies

"If I killed Travis, I would beg for the death penalty," Arias commented to a police detective in July 2008.
"If I killed Travis, I would beg for the death penalty," Arias commented to a police detective in July 2008.

Lies

"If I was going to ever try to kill somebody, I would use gloves. I have plenty of them," Arias told a police detective in July 2008.
"If I was going to ever try to kill somebody, I would use gloves. I have plenty of them," Arias told a police detective in July 2008.

Lies

"I'm all for the Ten Commandments — thou shall not kill," Arias told police in July 2008.
"I'm all for the Ten Commandments — thou shall not kill," Arias told police in July 2008.

Lies

"I understand all the evidence is really compelling ... I've never even shot a gun. That's heinous. I can't imagine slitting anyone's throat." Arias told the TV show "Inside Edition" in 2008, after she was indicted for killing Alexander.
"I understand all the evidence is really compelling ... I've never even shot a gun. That's heinous. I can't imagine slitting anyone's throat." Arias told the TV show "Inside Edition" in 2008, after she was indicted for killing Alexander.

Lies

"I don't have a gun ... I've never seen it ... I don't even know what a .25 looks like," Arias told police on July 15, 2008.
"I don't have a gun ... I've never seen it ... I don't even know what a .25 looks like," Arias told police on July 15, 2008.

Lies

"You sure it was me? I was not there. I didn't hurt Travis," Arias told police on July 15, 2008, when she was told authorities had photographic evidence that she was at Alexander's house the day he died.
"You sure it was me? I was not there. I didn't hurt Travis," Arias told police on July 15, 2008, when she was told authorities had photographic evidence that she was at Alexander's house the day he died.

Lies

"I'm not the brightest person, but I don't think I could stab him, I'd have to shoot him … The least I could do is make it as humane as possible," Arias told a police detective on July 15, 2008.
"I'm not the brightest person, but I don't think I could stab him, I'd have to shoot him … The least I could do is make it as humane as possible," Arias told a police detective on July 15, 2008.

Lies

"I don't think I've ever even fired a gun ... water guns, but not a real gun," Arias told police on July 15, 2008, when asked about the .25 caliber handgun used in Alexander's slaying.
"I don't think I've ever even fired a gun ... water guns, but not a real gun," Arias told police on July 15, 2008, when asked about the .25 caliber handgun used in Alexander's slaying.

Lies

"I think he was shot … I heard this loud ring – I don't remember. Travis was screaming. I know I got hit in the head … There were two people there … one was a guy and one was a girl … The girl wanted to kill me ... I was really scared. I was freaked out of my mind," Arias told police on July 15, 2008, after she finally admitted being at Alexander's home when he was murdered but denied she was involved in the killing.   Arias told police two intruders – white Americans with beanies covering their faces – killed Alexander and let her live.

Lies

"I think there was a naive belief that I could pretend [Alexander's murder] didn't really happen," Arias said in a 2009 interview with "48 Hours."
"I think there was a naive belief that I could pretend [Alexander's murder] didn't really happen," Arias said in a 2009 interview with "48 Hours."

Lies

“I couldn’t keep my stories straight. It’s all the same thing, just different versions – I couldn’t keep my lies straight,” Arias said on Feb. 27, 2013, while detailing her confusing web of deception.
“I couldn’t keep my stories straight. It’s all the same thing, just different versions – I couldn’t keep my lies straight,” Arias said on Feb. 27, 2013, while detailing her confusing web of deception.

Lies

"I understand that there will always be questions," Arias said on March 7, 2013, when she was asked by her attorney why, given all the lies she has admitted to, anyone should believe anything she says.
"I understand that there will always be questions," Arias said on March 7, 2013, when she was asked by her attorney why, given all the lies she has admitted to, anyone should believe anything she says.

Bloodshed

"It started where Travis was in the shower. I was taking photos of him [and] the camera slipped ... It fell onto the ground. He got very angry. He stepped out of the shower and lifted me up and body-slammed me … I ran down the hallway ... into the closet. I grabbed the gun [and] ran out ... I just wanted him to stop, so I pointed the gun at him ... He lunged at me right around the time the gun went off. I didn't mean for it to go off," Arias said of the events of June 4, 2008.

Bloodshed

"It was like mortal terror. I pissed him off the worst I'd ever seen him pissed off," Arias testified on Feb. 20, 2013. She was referring to Alexander allegedly attacking her on June 4, 2008, when she dropped his camera.  "I was scared ... He's freaking out. I'm freaking out," Arias said.
"It was like mortal terror. I pissed him off the worst I'd ever seen him pissed off," Arias testified on Feb. 20, 2013. She was referring to Alexander allegedly attacking her on June 4, 2008, when she dropped his camera. "I was scared ... He's freaking out. I'm freaking out," Arias said.

Bloodshed

“I didn’t choose to escalate it. I was trying to deescalate it," Arias said on Feb. 28, 2013.
“I didn’t choose to escalate it. I was trying to deescalate it," Arias said on Feb. 28, 2013.

Bloodshed

“The gun went off. I did not mean to shoot him or anything,” Arias testified on Feb. 20, 2013.
“The gun went off. I did not mean to shoot him or anything,” Arias testified on Feb. 20, 2013.

Bloodshed

"I was scared and I couldn't imagine calling 911 and telling them what I had just done," Arias testified on Feb. 20, 2013. "I was scared of what would happen to me."
"I was scared and I couldn't imagine calling 911 and telling them what I had just done," Arias testified on Feb. 20, 2013. "I was scared of what would happen to me."

Bloodshed

"The simple answer is that he attacked me and I defended myself," Arias testified on April 2, 2013.
"The simple answer is that he attacked me and I defended myself," Arias testified on April 2, 2013.

Bloodshed

"There's a morbid curiosity ... I mean I am curious," Arias told police when asked if she wanted to view the crime scene photos.
"There's a morbid curiosity ... I mean I am curious," Arias told police when asked if she wanted to view the crime scene photos.

Bad Memory

"There is a part of me that does not want to remember it ... [but] I feel like I am the person who deserves to sit with those memories that I don't have right now," Arias said on March 5, 2013, of Alexander's killing.
"There is a part of me that does not want to remember it ... [but] I feel like I am the person who deserves to sit with those memories that I don't have right now," Arias said on March 5, 2013, of Alexander's killing.

Bad Memory

"I can't explain why my mind did what it did ... I really don't know," Arias said on March 6, 2013, of why she had no memory of killing Alexander.
"I can't explain why my mind did what it did ... I really don't know," Arias said on March 6, 2013, of why she had no memory of killing Alexander.

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