John Allen, 36, was found guilty by a Denver jury Thursday of whipping his then-15-year-old son with an extension cord and forcing him to drink water spiked with bleach and soap in December 2008.
Allen will be sentenced Sept. 30 on the convictions for child abuse resulting in serious bodily injury and child abuse.
Allen has a separate pending child abuse case involving victims who were 8 and 7 years old at the time of the alleged incident.
He is awaiting sentencing in the Denver Detention Center, where he has been held since his arrest on a $20,000 bond.
Allen has been arrested several times on child abuse or similar charges. In 1999 he was pleaded guilty to a harassment charge after he was initially charged with sex assault on a child, records show.
