HONOLULU (HawaiiNewsNow) - Mark Matson was a Catholic priest in Hawaii and chaplain at Tripler Army Medical Center.
In 2000 he was convicted in Honolulu of sexually abusing a 13-year-old boy.
In the mid 1970s Matson supervised young boys at a Colorado seminary.
Court documents filed Tuesday in Denver allege he sexually assaulted one of them.
"Frequently during the evenings when our client was asleep in bed, he would approach our client's dormitory bed and proceeded to give our client oral sex on repeated occasions," said Adam Horowitz, attorney for the plaintiff.
The alleged victim is the John Doe in a civil suit against the Catholic order that ran the seminary. The plaintiff was fifteen at the time. He wanted to become a priest.
"Father Matson allegedly spiked our client's beverage and proceeded to rape him," Horowitz said.
The lawsuit said after the assaults, Matson left money under the teenager's pillow and later expelled him from the seminary.
In the 2000 Hawaii case, the prosecutor described Matson as "an individual who has a dark side to him."
Matson, 68, is serving a twenty-year sentence in the Halawa Correctional Facility.
"It wouldn't surprise me at all if there are additional allegations of abuse in Hawaii and elsewhere involving Father Matson," Horowitz said.
John Doe is now 49. He accuses the Catholic order of covering up by not telling him Matson was convicted in Hawaii and was suspected of sex abuse in California.
"Somehow, some way a court will have to decide how much this has cost my client in his life," Horowitz said.
Matson is a registered sex offender in Hawaii. In Colorado he is at the center of sex abuse case that is just starting to unfold.