Jordie Callahan and his girlfriend, Jessica Hunt, were convicted by jurors in federal court in Youngstown a day after their lawyers argued prosecutors had built their case around unreliable witnesses.
But prosecutors said the couple kept the woman and her daughter, who was under age 5, in a damp, dark basement with a lock on the door and no bathroom. The couple also threatened both with a python and pit bulls and forced the woman to shop, cook, clean up after their dogs and do other household chores, Assistant U.S. Attorney Chelsea Rice said.
Prosecutors said the woman also was forced to engage in sexual acts.
Callahan and Hunt were convicted on charges that included forced labor conspiracy with a kidnapping specification and could be sentenced to as much as life in prison. But they were found not guilty of stealing the woman's government benefits and tampering with a witness.
Hunt shook her head when the verdicts were announced. Her attorney, Ed Bryan, said, "There were a lot of horrific allegations made by the government in this case that we do not believe were supported by the evidence."
Callahan's attorney, Donald Butler, said he hopes to appeal.
U.S. Attorney Steven M. Dettelbach said the defendants "inflicted unspeakable cruelty upon this mother and her child."
"This case provides another stark reminder that human trafficking takes place all around us and that we need to be better neighbors to one another," he said in a statement.
Prosecutors said the woman's ordeal lasted from early 2011 to late 2012. Police in the northern Ohio town of Ashland first got involved when the woman was arrested on a candy bar shoplifting case and asked to be jailed because people had been mean to her.
The woman and her daughter were freed after police investigated an abuse allegation one of the suspects made against her. Authorities said that allegation was a ruse, complete with a video staged by the suspects. They said the suspects had forced the woman to act as if she were mistreating her child.
The woman later pleaded guilty to child endangering and was sentenced to about five months in jail but served only part of that.
Hunt's attorney accused investigators of sensationalizing what happened and using unreliable witnesses, including two who pleaded guilty in connection with the case. He said Hunt was only trying to help a homeless acquaintance by giving her a place to live and didn't force her to stay.
Callahan's attorney said that Hunt and Callahan used drugs and lived a different lifestyle but that didn't mean they mistreated the woman who lived with them.
"Even at the bottom of society, they relied on each other. That's all this was," Butler said.
But prosecutors said that when the woman was allowed to go shopping, the defendants threatened to beat the child if the woman spent too much money or didn't return quickly enough.
The two defendants who pleaded guilty earlier are scheduled for sentencing later this month.
Daniel Brown, who was accused of helping to enslave and beat the woman, pleaded guilty to a conspiracy charge. His plea required him to cooperate with investigators and testify.
Dezerah Silsby, who was accused of using ice cream to lure the woman and her child back into the home, entered her plea under the terms of a sealed agreement.
Silsby testified that Hunt threatened her and forced her to clean the couple's apartment and that she drove the woman and Hunt to an ATM to get money using the woman's government funds debit card.
The U.S. attorney's office said Silsby pleaded guilty to four counts of an indictment charging her with threatening the woman, beating her and making her do housework. An FBI affidavit said Silsby smashed the woman's hand with a rock so she could go to a hospital and bring back pain medication for the suspects.
The Associated Press isn't naming the woman or her daughter because prosecutors say the woman was a sexual-abuse victim.