An attorney for the adult Turpin siblings says they didn't have "adequate exposure to education"

David Turpin, the father accused of imprisoning and abusing his children in a California house of horrors, was charged Friday with eight counts of perjury on Friday, the Riverside County District Attorney’s Office announced on Twitter.

According to the announcement, from 2010 to 2017, Turpin “certified under penalty of perjury that the children in the home were receiving a full-time education in a private day school.”

David, 59, and Louise Turpin, 49, were arrested on Jan. 14 after their malnourished 17-year-old daughter climbed through one of the windows of their Perris home and called 911 using a disconnected cell phone and told authorities she and her 12 siblings were being abused by their parents.

Responding officers found what they have called a scene of malnutrition and squalor at the Turpin residence, with some of the children chained to the furniture. Prosecutors allege the parents beat, strangled and starved the kids in an intensifying cycle of abuse dating back to at least 2010.

DA's Office Announces Charges Against California Couple Who Held 13 Kids Captive
David Turpin
| Credit: Terry Pierson-Pool/Getty Images

At the time of their parents’ arrest, the children ranged in age from 2 to 29.

The California couple have since pleaded not guilty to torture, abuse, and false imprisonment charges.

They face up to life in prison if convicted on all charges.

• To learn more about Louise Turpin’s life with her sister Elizabeth Flores, subscribe now to PEOPLE or pick up this week’s issue, on newsstands Friday.

The Turpin family
Credit: A Elvis Chapel in Las Vegas

The lawyer for the seven adult Turpin siblings told PEOPLE in March that the siblings had been released from their months-long stay in the hospital and were in a new home, and that they looked forward to going to school, getting their GEDs and even attending college.“None of them has had what I think anyone would consider adequate exposure to education, and that is what we are trying to remedy right now,” Caleb Mason, the attorney, said.

He described the siblings as “bright and articulate and incredibly eager to study.”

The first step, Mason said, will be obtaining their GEDs or high-school diplomas. He is working with local university officials to “put together an educational plan for all of them” and says the siblings “for the most part have not had any kind of formal schooling.”