Alexander, a motivational speaker and entrepreneur, was found dead in the shower of his Mesa home, his throat sliced from ear to ear, his body stabbed 27 times and his face disfigured by a gunshot wound.
Arias initially told police she was not involved in Alexander's death. She changed her story and told police two people broke into his home, killed him and attacked her. The story changed a third time when she said she killed Alexander in self-defense.
Police said Arias and Alexander, 30, had been dating on and off when she moved to Mesa to be closer to him.
Prosecutors claim Arias killed Alexander out of jealousy after he tried to end their relationship.
Police said they found potentially damning evidence during their investigation. A camera was found in a washing machine. Police said someone erased the memory card, but police were able to recover the photos.
There were three photos police believe were inadvertently taken, showing Alexander's lifeless body, time-stamped just minutes after images showing the two naked together in his home.
On Wednesday, the prosecution said one of Alexander's friends went to check on him after not hearing from him and found him dead on June 9.
Prosecutor Juan Martinez claimed the crime scene was manipulated by Arias. Martinez said Alexander's body was found in the shower, but his murder took place somewhere else in the home. Martinez told jurors that Alexander was stabbed while he tried to defend himself. The killer dragged him toward a sink and then shot him.
Prosecutors suggested that Arias stole a gun from her grandfather to kill Alexander. Prosecutors said two days before the murder, Arias went to Yreaka to rent a car. She changed her hair color between June 2 and June 4 and returned the car a day late on June 7.
"This love, well she rewarded that love for Travis Victor Alexander by sticking a knife in his chest," Martinez said during his opening statement.
Defense attorney Jennifer Willmott told jurors on Wednesday that Alexander was a controlling man who was verbally abusive to Arias. The defense claimed that Arias believed Alexander was going to kill her and that she killed him in self-defense.
"He lunged at Jodi in anger, knocking her to the ground in the bathroom, where there was a struggle," Willmott said in her opening statement. "Jodi's life was in danger."
Arias got emotional in court Wednesday afternoon as a Mesa police officer described the scene of the crime.
FBI profiler Candice DeLong told CBS 5 News in July 2011 that people shouldn't rush to judgment and follow the flock of people asking why the case is even going to court.
"I think we all said that about Casey Anthony, too, so we need to watch out," DeLong said.
But she added, "I would love to hear her explanation of how those photographs of them intimately engaged were so closely time-stamped."
"It'll be fascinating to hear what her explanation, or her attorney's explanation, of that is," DeLong said.
On Monday, a friend of Alexander's, Marie Hall, testified about the night she and some friends discovered the body. She wanted to check up on him because he wasn't answering her calls or messages; they were supposed to go on a trip to Cancun in the coming days.
"The roommate ran out and said, 'he's dead, he's dead,' and so immediately I called the police," she said.
Mesa Police Officer Sterling Williams, who responded to the scene, testified Monday, describing the scene as well as Alexander's wounds.
"He was kind of crammed into the bottom of a shower stall," Sterling Williams said.
Prosecutors said they are going for the death penalty. There are three women currently on Arizona's death row.
Eighteen jurors will hear the case and 12 jurors, made up of 11 men and seven women, will deliberate.
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