The parents of 13 children allegedly held captive in their California home have pleaded "not guilty" to charges of "torture, child abuse, and false imprisonment".
Prosecutors said the victims were "beaten, starved, and chained".
David Turpin, 57, and his wife Louise Turpin, 49, who appeared in court for the first time on Thursday, each face 94 years to life in prison if convicted.
David Turpin was also charged with one count of committing a lewd act on a child by force or duress, according to Riverside County District Attorney Michael Hestrin.
Hestrin told reporters the couple had allegedly punished their children by tying them up - first with ropes and later with chains and padlocks.
The alleged punishments would last weeks or months, with circumstantial evidence showing that the children were not released from their chains to go to the toilet.
"They lacked a basic knowledge of life," he said of the Turpin's 13 children, aged between two and 29.
The California Department of Education lists the Turpin's Perris address, where the family has lived since 2014, as the location of the Sandcastle Day School, and David Turpin as principal.
The 13 siblings have been receiving hospital treatment since Sunday when one of them, the couple's 17-year-old daughter, climbed out of a window and called police, having planned the escape for over two years, according to prosecutors.