TOMS RIVER, N.J. (CBSNewYork/AP) — A prosecutor says a New Jersey man knew police were coming to arrest him on outstanding warrants when he opened fire on a young patrolman who sought to question him.

At the start of Jahmell Crockam’s murder trial in Toms River Wednesday, Chief Assistant Ocean County Prosecutor William Heisler said the defendant had vowed several times to friends that he would sooner kill a police officer than go to jail.

Prosecutors say Crockam shot Patrolman Christopher Matlosz after the officer drove up alongside him on August Drive last January.

Crockam then allegedly opened fire, shooting the 27-year-old officer three times at close range.

“On Jan. 14 last year, that man, the defendant Jahmell Crockam, in broad daylight and in cold blood, executed Officer Christopher Matlosz of the Lakewood Police Department,” said Chief Assistant Ocean County prosecutor William Heisler, pointing accusingly across the courtroom at the now-20-year-old Crockam.”The defendant was trying to avoid arrest and that’s why he committed this murder.”

Crockam’s lawyer, Mark Fury, got straight to the heart of his defense in the first two words of his opening statement.

“Says who?” he asked the jury.

He said several prosecution witnesses are admitted criminals who have every incentive to testify untruthfully.

“You are going to see the most remarkable display of the most unsavory characters, each of whom has the most piquantly delicious motive to lie that I have ever seen,” Fury said.

Other witnesses, while well-meaning, simply cannot identify the shooter with certainty, Fury added. He said five people wearing dark clothing similar to what Crockam had on were on the street that afternoon.

“There ain’t no gun. There ain’t no DNA,” he said. “There ain’t no good fingerprints. There ain’t no good witnesses. Officer Matlosz was killed by a guy in dark clothing. And that’s all they have.”

To avoid prejudicing the jury, prosecutors didn’t say in court what charges were contained in the outstanding arrest warrants in effect for Crockam. But immediately after the killing last year, authorities said Crockam was being sought on illegal weapons charges. On Dec. 29, 2010, the prosecutor’s office obtained an arrest warrant for him on charges of possessing an illegal rifle and hollow-point bullets.

The first prosecution witness, Lakewood police Sgt. Steven Vigna, testified that he was the patrol supervisor that afternoon and heard a radio call reporting shots fired. He sped to the scene and found Matlosz’s police cruiser parked in the street with the driver’s side door open. Inside the vehicle, the officer was slumped to the side, his head lolling down on his chest.

“His shirt was covered in blood,” Vigna testified. “There was blood about his face, dripping from his nose. There were no signs of life. His head was down and his eyes were closed.”

The prosecutor told the jury that Crockam pulled a .38 caliber handgun from his pocket and shot the officer once in the back of the neck. He then reached the gun into the patrol car and fired into the officer’s face.

“Then, to make sure he was dead, he put the gun a few inches from his head and fired a shot into Officer Matlosz’s temple,” Heisler told the jury.

Vigna testified that he was assigned to drive an ambulance with the fatally wounded officer in the back to Jersey Shore Regional Trauma Center in Neptune. He knew Matlosz was already dead after paramedics tried in vain to revive him. But a doctor had to pronounce him dead at the hospital.

Vigna retrieved the officer’s gun, the keys to his car and some personal effects and stored them in a locker at police headquarters.

Heisler said Crockam had confessed several times to acquaintances that he shot and killed the officer. He acknowledged to the jury that some of those witnesses “may not be from your world.”

“You may hear about lifestyles you don’t like,” he told the jurors. “The question here isn’t whether you like them or not; the question is whether you believe their testimony.”

After the jury was dismissed for lunch, Superior Court Judge Wendel Daniels agreed to allow jurors to hear evidence that Crockam admitted killing the officer to three fellow inmates in the Ocean County Jail while awaiting trial.

“He told more than one person on more than one occasion that he would shoot a cop, kill a cop before he would go to jail,” Heisler told the jury.

Matlosz was on his first day of the afternoon shift after transferring from night patrol. He was also engaged to be married.

Before joining the Lakewood Police Department, Matlosz worked as a police officer in Englishtown, a Monmouth County suburb, and as a Class 2 special police officer in Freehold Township, Manasquan and Long Branch on the Jersey shore.

He graduated from Howell Township High School and earned his degree in criminal justice from Brookdale College in 2004.

His death was the second shooting incident involving a Lakewood police officer in recent years.

(TM and Copyright 2012 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2012 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

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