TWIN FALLS - A Twin Falls dad will spend the rest of his life in prison for killing his three young children late last year.

Twin Falls Police

Jim Junior Nice will be arraigned today on three counts of first-degree murder in the deaths of his children.

Jim Junior Nice pleaded guilty to three counts of first-degree murder in a Twin Falls County courtroom Friday morning. 

The 33-year-old was arrested in December 2005 and is accused of using rat poison and over-the-counter medications to poison his 6-year-old twin sons and 2-year-old daughter. 

The young children were found dead inside Nice's Twin Falls home after a co-worker reported their father didn't show up for a scheduled shift at work.   

When police went to check on the family -- they found the children and a distraught nice who told officers he poisoned his children so they wouldn't have to suffer through their parent's divorce.  

Nice and his wife were divorced early 2005 and shared custody of their children.

Jim Nice is accused of killing his three children with rat poison.

In addition to the murder charges -- Nice pleaded guilty to what are called aggravating circumstances. Under Idaho law, Nice will automatically be sentenced to three life sentences without the chance of parole.  

As part of the plea deal -- the defendant is also required to waive all appeals of the conviction or the sentence. 

Prosecutor Grant Loebs called the plea a horrendous crime.  He says Nice's life sentences will ensure justice for each of the three children -- ensuring this man dies in prison.