The key prosecution witness in the "execution-style" murder case against Patrick Deguair Jr. took the witness stand yesterday, first describing what life is like for an inmate in the state's witness protection program.

David Teo, 46, has pleaded guilty to robbery and firearms charges and agreed to testify against Deguair, who is charged with murdering Jermaine Duckworth last year.

Under questioning from Deputy Prosecutor Scott Bell, Teo said he's given $500 per month in expense money, which he uses to order food he cooks for himself in his cell.

Teo said he has a television, "basic cable" and a DVD player in his cell at an undisclosed location. The cell is roughly 11 feet by 14 feet in size and has an "attached bathroom" but no shower, Teo said.

He spends 16 to 17 hours a day in his cell and is allowed outdoor recreation once or twice a week, Teo said.

The witness can make three 15-minute telephone calls each day, which are monitored by his jailers, Teo said.

Deguair's lawyer, Neal Kugiya, said in his opening statement that Teo is the real killer of Duckworth, 24, who was shot in the back of the head with a silenced .22-caliber pistol and thrown off a Leeward Coast cliff March 27, 2008.

But Teo denied those allegations, telling the jury that he watched from a parked car and saw Deguair fire the handgun point-blank into Duckworth's head, then simultaneously push and kick the body over the cliff at Kaena Point.

Duckworth's mouth had been sealed with duct tape and his hands had been taped together behind his back, according to Teo.

When Deguair came back to the car, he said, "We should kill all the rats" to another man in the car, Ju Young Woo, Teo said.

Prosecutor Bell has argued to the jury that Deguair shot Duckworth because he suspected him of being a police informant.

Teo claimed that he barely knew Duckworth and did not know Deguair planned to murder him.

Teo said he met Deguair, Woo and Duckworth earlier in the evening at a house in Waipahu, smoked crystal methamphetamine with them and agreed to accompany them when they left in a car.

Teo said Deguair gave him the gun after the shooting and asked him to "get rid of it."

Teo sold the gun for $150. Police later recovered the weapon.

Kugiya told jurors that Teo killed Duckworth because he believed the victim had stolen from friends of Teo who lived in Nänäkuli.

Teo denied those allegations, saying he has no friends in Nänäkuli.

Teo has agreed to serve up to 20 years in prison for his guilty pleas but agreed with Kugiya that he "could be released much sooner than that."

The trial, in Circuit Judge Michael Town's court, resumes this afternoon.