9NEWS is not naming the mother because it could identify her daughter.
A judge sentenced the mother to 20 years after she pleaded guilty to forcing a child into prostitution and sentenced her to another 12 years for contributing to the delinquency of a minor, according to Colorado criminal court records.
After a day-and-a-half of deliberations, a jury Thursday found one of the customers, Ronald Webster, guilty of two counts of sexual assault on a child, one count of sexual assault by a person in position of trust, contributing to the delinquency of a minor and distribution of a controlled substance, according to the Denver District Attorney's office. He'll be sentenced in September.
An affidavit says 53-year-old Webster, who lived upstairs from the mother and daughter in an apartment complex on Winona Court, threatened the 13-year-olds.
"If you tell police, I swear to God, there's something bad going to happen to you," he said, one of the victims told Denver Police.
The girls were 13 years old when the mother coerced them into conducting sex acts with men in exchange for money and drugs. The mother gave the girls clothing, food and shelter for having sex with the men.
The mother smoked crack and meth with the girls before she prostituted them out, according to the affidavit.
One of the victims - now 14 years old - told Denver Police she had sex with the men for drugs or money about 100 times when she was 13 years old. She says she charged them $40 to $60 each time for sex. The victims say most of the men were East Side gang members.
The prostitution lasted for about a year until one of the girls got pregnant, according to the affidavit. Adams County Social Services removed the girls from the woman's custody.
A criminal background check shows that Webster has been in and out of prison since 1976 for burglary, assault, stealing cars, homicide, sexual assault, strong-arm rape, larceny, resisting police, and disturbing the police. His sentencing is set for Sept. 29.
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