Camp Verde, Arizona (CNN) -- The eighth day in the trial of a formal spiritual retreat leader charged with manslaughter after a deadly sweat lodge ceremony concluded Friday with emotional testimony from the roommate of one of the victims. Self-help author and James Arthur Ray is accused of three counts of manslaughter in the deaths of three people who were in the sweat lodge for the purification ceremony. If convicted, he could face up to 10 years in prison on each count. Witness Beverley Bunn, who roomed with victim Kirby Brown during the five-day retreat in 2009, went through an exhaustive examination Friday, recounting all eight rounds of the sweat lodge purification ceremony. Each round lasted 10 to 15 minutes. While they were not prevented from leaving, participants have said they were encouraged to wait until the breaks between rounds.
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Beverley Bunn roomed with one of the three victims at the 2009 retreat
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Self-help author and retreat leader James Ray is charged with manslaughter
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Defense calls the incident "a tragic accident"
@placeholder is scheduled to return to the witness stand when the trial resumes Tuesday.