BARNSTABLE, Mass. (AP) – Jurors deliberating the fate of a trash collector accused of murdering a Cape Cod fashion writer asked for clarification Friday on the legal concept of reasonable doubt.

The panel met for its fourth day in Barnstable Superior Court, but went home for the weekend without reaching a verdict.

Christopher McCowen, 34, is charged with raping and killing Christa Worthington on Jan. 5, 2002, in her Truro home.

The jurors asked Judge Gary Nickerson to redefine the legal theory of reasonable doubt and the parameters of legal doubt. The judge reiterated the guidance he provided in his original charge to the jury on Tuesday. The jury did not ask any further questions before calling it quits for the day.

Prosecutors insist McCowen acted alone and made up a story about his friend being the real killer.

Jurors have been instructed that under the state’s joint criminal venture theory, they could convict McCowen even if they believe the story that he gave police that Jeremy Frazier fatally stabbed the victim. Frazier was not charged and said he was not at Worthington’s home the night she was killed.

Under the theory of joint venture, someone who actively assists another person in committing a crime is considered just as responsible for the crime. Under the theory, the person who assisted must share the same mental state or have the same intent as the person who actually commits the murder.

McCowen has said he had consensual sex with Worthington. He also told police he helped Frazier beat her, that he watched as Frazier killed her and that he helped Frazier wipe down her body then beat her.

In a lighter moment at the end of Friday’s deliberations, Nickerson urged jurors to enjoy their “customary pursuits” over the weekend and come back Monday morning refreshed and ready to go back to work.

“If somehow your work here this week has somehow left you empowered with a feeling that you’re ready for new challenge, if you’ve never gone hang-gliding, this is not the weekend to do it,” Nickerson said, which evoked chuckles from the jury.

McCowen’s father, Roy McCowen, told Court TV on Friday that his son was “doing OK,” but was also on a “roller coaster of emotion.”

“One day he is feeling good and one day he is feeling down because he hears everything. He knows he has a tough road to climb,” McCowen told the network.

Jury deliberations resume Monday morning.