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Ashton Kutcher has testified in the trial of suspected serial killer Michael Gargiulo who is allegedly connected to the murder of a woman Kutcher was dating in 2011.

The actor, now 41, had planned to go to dinner and drinks with 22-year-old Ashley Ellerin on the evening of February 21 2001 after meeting her some months prior. It would be their first date as both had just become newly single. Kutcher had spoken to Ellerin on the phone at around 8.30pm that evening to confirm their date but when he tried to reach her multiple times to check her whereabouts, she didn’t answer her phone. Kutcher then went to her home between 10.30pm-10.45pm and nobody answered the door despite the lights being on.

Prosecutors have previously said that Kutcher peered through the front window of the house and could see what he believed to be red wine stains. Police believe the stains were blood. “I saw what I thought was red wine spilled on the carpet. But that wasn’t alarming because I went to her house party [days before] and it was like a college party,” said Kutcher in court. “I didn’t think much about it.”

The actor said he believed he was stood up and just “assumed [Ellerin] had gone out with her friend and bailed.”

Ashley Ellerin – in white front and centre – with friends.

The victim’s friends have also testified noting how Gargiulo – who lived just a block away from Ellerin – would show up at her house uninvited and would park outside her home at odd hours. Prosecutors believe Ellerin was getting ready to meet Kutcher and had just finished having a shower when she was attacked from behind.

When Kutcher realised the next morning that his date had been murdered, he said he was worried during his interview with police because he had touched her front door. “My fingerprints are on this door and I was freaking out,” he said. “I told [an officer], ‘Let me tell you what happened.’”

He was on the stand for 40 minutes.

Gargiulo is also charged with the 2005 stabbing murder of 32-year-old Maria Bruno and the attempted murder of 26-year-old Michelle Murphy, who was viciously stabbed in her Santa Monica home in 2008. He also faces a murder charge in Illinois in the death of 18-year-old Tricia Pacaccio, who was found stabbed to death outside her Glenview home in 1993.

Prosecutors are seeking the death penalty. Gargiulo has pleaded not guilty.