A Californian couple accused of beating, shackling, starving and imprisoning their 13 children pleaded not guilty on Friday.

David and Louise Turpin face dozens of charges of torture, false imprisonment and abuse and could face life in prison if found guilty.

Police raided the Turpins' home in Perris in January, after an emaciated 17-year-old girl escaped through a window and called 911.

Officers found the girl's 12 brothers and sisters - ranging in age from 2 to 29 - trapped inside the darkened, foul-smelling house, with some even chained to beds.

David and Louise Turpin pleaded not guilty to torturing, abusing and imprisoning their children

The siblings, suffering from malnourishment, muscle wasting, stunted growth and other signs of severe abuse, were taken into protective custody and their parents were arrested.

Prosecutors have said the victims were deprived of food, basic hygiene and medical care.

It has also been claimed the children were harshly punished for trivial reasons, such as wasting water by washing their hands above the wrist, and even taunted with food they were forbidden to eat.

Defence lawyers are yet to offer an explanation for the circumstances alleged by authorites.

David's parents described the couple as 'deeply religious' (
Image:
Barcroft Media)
Louise and David reportedly required their children to memorise Bible passages (
Image:
Getty Images North America)

Described as 'a deeply religious' couple, the Turpin's home-schooled their children and made them memorise Bible scripture, according to David's parents, James and Betty Turpin.

The defendants were each charged with 12 counts of torture, 12 counts of false imprisonment, seven counts of abuse of a dependant adult and eight counts of child abuse.

Louise Turpin, 50, also faces an additional assault charge.

Authorities were alerted to the home after one of the daughters escaped through a window (
Image:
Sunday Mirror)

David Turpin, 56, a former aeronautics engineer, was also charged with one count of committing a lewd act on a child, plus eight counts of perjury over his claims of running a private school, with his children as the students.

The couple entered a not guilty plea to all charges and denied all allegations.

The couple appeared in court on Friday (
Image:
AFP)
The trial will reportedly begin on Oct. 5 (
Image:
AFP)

Judge Bernard Schwartz denied a defense motion to try the perjury counts separately from the other charges.

The trial will begin on October 5.