A state appeals court on Thursday denied the 33-year-old inmate's bid to leave prison before his term of 78 years to life is up, PennLive reports. He will not be eligible for parole until he is 103 years old.
Mull was convicted of rape and human trafficking after a single trial in 2018.
The three victims -- between 19 and 25 years old -- said he held them captive, strangled, beat them, forced them to take drugs and threatened to tell their families.
Mull, of Lower Saucon Township, treated the victims like sex slaves, binding them and ordered them to call him "master," PennLive reports.
The incidents reportedly occurred at Mull's apartment, and in hotels across Northampton County and Philadelphia.
Earlier this month, Mull was found guilty earlier this month of promoting prostitution in prison, the Northampton County DA's Office said.
Those charges stem from a 2019 incident in which he used a tablet he rented from the county jail to solicit a 27-year-old woman for prostitution, authorities said.
Mull was acquitted of charges accusing him of raping a fourth accuser but, was convicted of other sex crimes and assault against her, PennLive says.
“He is a predator," Bethlehem Police Chief Mark DiLuzio told CBS2 in 2017. "And that’s something I personally don’t like and anybody else who has children out there."
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