Juan Martinez, the prosecutor in the sensational Jodi Arias case, has broken his silence about the convicted murderer. Martinez penned a tell-all book, “Conviction -- The Untold Story of Putting Jodi Arias Behind Bars.” In the shocking 2008 case, Arias stabbed her ex-boyfriend, Travis Alexander, 27 times, slit his throat from ear to ear and then shot him. She claimed it was self-defense.

Arias thought she would get away with murder because of her level of intelligence. “Jodi Arias believed that if her I.Q. was measured it would be something like in the area of Albert Einstein. So, she probably thought that she could get away with it,” prosecutor Juan Martinez told Inside Edition Friday.

“What she did to Travis Alexander was absolutely horrific. The act of taking the knife and sticking it in his chest, and sliced his throat while he was still alive, that speaks to horrific overkill,” he said.

jodi arias Jodi Arias (left) and her attorney Jennifer Willmott look back during sentencing hearing in Maricopa County Superior Courtroom in Phoenix, April 13, 2015. Photo: Reuters/Mark Henle/Arizona Republic/Pool

Martinez recalled the scene of the crime in his book. "I immediately noticed a large amount of blood on the carpet bordering the hallway leading to the bathroom," Martinez said, according to Radar Online.

The bathroom, where Alexander was found in the shower, was “chaos.” The prosecutor wrote: Alexander's dead, naked body, "legs bent to his chest, head pressed onto his right shoulder, feet pushing against the wall."

Arias killed Alexander because he wanted to end their relationship. “Jodi Arias wanted to have Travis for herself. He didn’t want to see her anymore. So what she decided was, he wasn't going to be able to do that to her,” Martinez told Inside Edition. “Killing somebody is not love. It's just a show that this person belongs to you and that if you can't have them, nobody else will.”

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