Fighting back tears, Mack said she had joined Nxivm, led by self-described spiritual guide Keith Raniere, a decade ago to find objective in life. Prosecutors also allege that the leader of the group, Keith Raniere, established a secret sex cult within the organization, in which "slaves" were branded in their pelvic areas with his initials.
"I believed Keith Raniere's intentions were to help people", Ms Mack said in court on 8 April.
"I must take full responsibility for my conduct and that is why I am pleading guilty today", she said as she sobbed before apologizing to her family. I am very sorry for my role in this case. Jury selection as scheduled to begin shortly in her case.
With jury selection beginning at the federal case against a cult-like upstate NY group, TV actress Allison Mack pleaded guilty Monday to charges she manipulated women into becoming sex slaves for the group's spiritual leader.
There was no mention at the plea hearing of any agreement by Mack to cooperate with prosecutors against Raniere, who is expected to go on trial later this month. Until the Salzmans' guilty pleas, officials and associates had repeatedly denied all wrongdoing and disputed allegations that it is a cult.
Others charged in the case include Raniere and Clare Bronfman, an heiress to the Seagram's liquor fortune.
Mack is best known for her role as a young Superman's close friend on the series "Smallville". "Determining the truth is extremely important to me, and I can say firmly that neither NXIVM nor Keith have abused or coerced anyone".
Ms Mack had previously pleaded not guilty in April 2018 to charges including sex trafficking, conspiracy to commit sex trafficking and forced labour.
Her plea change also comes after NXIVM co-founder Nancy Salzman and her daughter Lauren Salzman pleaded guilty to racketeering and conspiracy charges. If convicted, he could be sentenced to life in prison.