TRUE CRIME: The fashion writer who was brutally murdered in her own home.

The small Cape Cod town of Truro is known for its quiet beaches, sunsets, and spectacular shell fishing.

It used to be the kind of community where everyone knew each other and no one even bothered locking their doors at night.

In the late 1990s it became a haven for Christa Worthington, a 46-year-old fashion writer who was looking for a quieter life after living in New York for almost twenty years.

She settled down in the small community, fell in and out of love, and eventually started a family on her own, giving birth to her daughter, Ava, in 1999.

But her little slice of paradise didn’t last long. On January 6, 2002, Worthington was brutally raped and murdered in her own home.

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Tim Arnold, a neighbour and former flame, would discover her lifeless body on her lounge room floor. Little two-year-old Ava was found clinging to her beaten, bloody mother. The toddler was distressed, hungry and tired, but unharmed.

Worthington’s murder, and the subsequent investigation and conviction, is now the subject of the true crime documentary and podcast A Killing On The Cape. 

The documentary-makers have delved deep into the case that shook the quiet Cape Cod community to its core and redefined their idea of safe.

The one thing the police were never short of during the investigation into Worthington’s murder was suspects. All up they investigated five different men who had varying degrees of involvement in Worthington’s personal life.

Their first suspect was Tim Arnold, the man who found Worthington’s body and also happened to be her former live-in boyfriend. Arnold told the police he had gone to Worthington’s house to return a flashlight he had borrowed.

The police interrogated Arnold for hours. At first, he denied having any further romantic interest in Worthington, saying that he only maintained their friendship so he could continue to be a part of little Ava’s life.

After hours of interrogation, Arnold finally admitted that he had still held out hope that the romance between himself and Worthington would be rekindled. He was eventually ruled out as a suspect.

Their second suspect was Thomas Churchwell, a New York City-based magician known as “The Amazing Tarquin”. Churchwell and Worthington had briefly dated back into 1998. Police interrogated Churchwell about his whereabouts at the time of the murder but later cleared him.

Next the police turned their attention to Ava's biological father, Tony Jackett.

Jackett was the shellfish constable of Provincetown and Truro. He was married to Susan Jackett and they had six kids together. He met Worthington in the summer of 1997 and they soon began to have a secret affair.

Worthington eventually became pregnant with Jackett's baby. The pair initially decided to keep the affair and the baby a secret, but later Worthington changed her mind and forced Jackett to tell his wife.

Susan was angry when she first heard the news but she eventually forgave her husband and his former mistress and welcomed little Ava into their lives. The relationship between Worthington and the Jacketts was always amicable.

The police soon cleared Jackett as a suspect.

Their next suspect was Worthington's own father, Christopher 'Toppy' Worthington. Christa's father was a Harvard educated lawyer and former prosecutor for the state attorney's office.

At the time of his daughter's murder, Toppy, then 72, was in a relationship with a 29-year-old woman named Elizabeth Porter. Porter was former prostitute and heroin addict and Christa did not approve of their relationship and hated the fact her father was financially supporting Porter.

But Toppy was also cleared as a suspect in the murder.

In the end, the fifth and final suspect was a man who Worthington barely knew.

His name is Christopher McCowen and he's currently serving three concurrent life sentences in prison after being found guilty of first-degree murder with extreme atrocity, aggravated rape, and aggravated armed burglary at Worthington's murder trial.

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McCowen worked as a garbage man in Truro and was one of several men who gave police a sample of his DNA during their investigation into Worthington's brutal murder. He was arrested in 2005 after that DNA matched the DNA found on Worthington's body.

At first McCowen denied knowing Worthington. Then he admitted to having consensual sex with Worthington at her house on the night the police believe she was murdered.

He later claimed another man, Jeremy Frazier, was at the house that night. McCowen told police both he and Frazier had beat Worthington, but Frazier had ultimately killed her.

Police believe McCowen acted alone that night and there's never been a clear motivation for the crime. McCowen continues to maintain his innocence behind bars.

It's been 15 years since the murder of Christa Worthington, and the small community of Truro is still struggling to understand how such a brutal and random crime could occur in their sleepy little neighbourhood.

You can listen to the first six episodes of A Killing On The Cape on iTunes. 

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