By Megan Tench, Globe Staff
BARNSTABLE -- Tim Arnold, former boyfriend of fashion writer Christa Worthington, testified yesterday that he had trouble controlling his anger during their relationship and acknowledged that he was once a key suspect in Worthington's slaying.
As jurors feverishly scribbled in their notebooks, Arnold, 48, said in response to questions from defense lawyer Robert A. George that suspicion cast by police and others plunged him into a suicidal depression.
Arnold told jurors that after he had been given medication and admitted to a Cape Cod psychiatric facility in 2003, two Massachusetts State Police officers would not relent, following him into his hospital room, peppering him with questions, and pressuring him to confess while he lay in his pajamas in bed.
``They thought I was the killer," Arnold said as he stood in the witness stand at Barnstable Superior Court.
The former children's book author's description of how he was treated by police appeared to support George's argument that his client, Christopher M. McCowen, was manipulated and forced into a false statement by investigators who were determined to solve the crime regardless of the facts.
After his DNA matched evidence found on Worthington's body, McCowen, a 34-year-old garbage collector, told police that he was at Worthington's Truro home at the time of her January 2002 slaying and that he had consensual sex with her and beat her, but that a friend killed her, prosecutors have said.
McCowen is charged with burglary, aggravated rape, and murder and faces life in prison if convicted in the high-profile trial that is drawing national media coverage.
Police only concluded that the 46-year-old heiress was raped because McCowen is black and uneducated and they could not conceive of Worthington agreeing to have sex with him, George said in his opening statement Wednesday.
Under cross examination by George yesterday, Arnold testified that Worthington had relationships with individuals who were not ``men of status." And he detailed for jurors his own turbulent relationship with Worthington, which often led to heated arguments.
Arnold, who discovered Worthington's body in a pool of blood in her kitchen, said he did not know until last week that a brown blanket, which was used to cover her, was stained with his semen.
Arnold's father, Robert Arnold, 81, who was sitting outside in his car when his son found the body, testified yesterday that he comforted Worthington's then-2-year-old daughter Ava who was smeared with her mother's blood.
Jan Worthington, Worthington's cousin and a volunteer emergency medical technician who responded to the scene, described in vivid detail her horror at seeing her cousin dead.
``I saw my cousin laying on the floor," she said, appearing to be on the verge of tears. ``Her legs were pulled apart."
Jan Worthington, who is also a movie screenwriter, said under cross examination that soon after the homicide she sold the movie rights to the story of the slaying to cable television's Lifetime channel and agreed to make a documentary with HBO.
So far she has been paid $60,000. Both projects have yet to be completed.
Jan Worthington said she wanted to prevent others from exploiting her cousin's death. When George asked how quickly she sold the rights, Worthington responded, ``As soon after the murder as I could."
Megan Tench can be reached at
mtench@globe.com. 
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