Someone accessed Travis Alexander’s cell phone voicemail shortly after he was killed.

Telecommunications expert Jody Citizen (pictured below) testified Tuesday in the Jodi Arias trial that someone listened to Alexander’s voicemail four times after 5:30 p.m. on June 4, 2008, the estimated time of his death.

If prosecutors can connect Arias to checking Alexander's voicemail, it could provide a motive that that they could use to explain why she allegedly killed him. She has, of course, claimed she killed him in self-defense, after he brutalized her.

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Citizen works for Verizon Wireless, and said that whoever checked Alexander’s voicemail also had to know his pin number to access the messages.

In a recorded conversation played for the jury last week, Arias admitted to Mesa, Arizona, police Det. Esteban Flores that she checked Alexander’s phone  in the past for text messages from other girls. She also told Flores that the text messages prompted her to break up with him, but they continued to have a sexual relationship.

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Soon after Alexander’s body was found in June 2008, Arias told police she was not involved in Alexander's death. She later changed her story and told investigators that she witnessed two intruders break in and kill him. She eventually admitted to killing Alexander, saying it was in self-defense.