A fellow inmate has testified that Timothy Nicholls of Colorado Springs admitted setting the fire that burned his three children to death in 2003.
Hiram Church, Nicholls' cellmate in 2005, said Friday that he befriended Nicholls and got him to reveal details of the fire.
Defense lawyer Dennis Hartley said Church was lying to get out of jail early.
He is imprisoned for aggravated robbery and pimping.
Prosecutors alleged Nicholls set the fire to collect on a 250-thousand-dollar insurance policy.
They allege the family was deeply in debt.
The three children, eleven-year-old Jay, five-year-old Sophia and three-year-old Sierra died in the fire that destroyed their home March 7th, 2003.