Prince George's County police officers reacted angrily yesterday to a jury's decision, after 40 hours of deliberation, to spare Harlow Brian Sails from the gas chamber and instead sentence him to life in prison for the murder of a county policeman during a jewelry store holdup last year.

"What do you have to do in this country to get a just reward?" asked Officer Clifton Brinkley, who worked with the murdered police officer, Raymond Hubbard, at the county police Oxon Hill station. "I'm angry and disappointed," Brinkley said.

John Porter, another officer who was a close friend of the 26-year-old Hubbard, said yesterday, "The decision that was made last night affects more than the police, it affects everybody. This won't deter anyone from holding up a drug store."

As the jurors left the courtroom Friday morning, about 20 officers lined the corridor and deliberately stared each juror in the eye. "Thank you," one officer said sarcastically to each juror as they passed.

Last January, the same jury convicted Sails of murdering Hubbard, who was off duty on Feb. 8, 1982, when he attempted to stop Sails as he fled from the Kay Jewelers at Iverson Mall which Sails and four others had just robbed.

The jury began deliberating whether to send Sails to the gas chamber at 9 a.m. Wednesday and finally returned with their decision at about 2:30 a.m. yesterday.

Circuit Judge Howard S. Chasanow ordered the life sentence to run consecutively with a 70-year sentence sentence he handed 21-year-old Sails earlier this week for related offenses stemming from the jewelry store robbery. Sails will not be eligible for parole for 29 years.

Chasanow told police officers after the verdict "The only thing I can assure you of is he will never get out."

Sails showed no reaction when the verdict was read read, but his mother, Mildred Mims, sitting in a corner of the crowded courtroom, smiled and nodded her head. "I'm satisfied with the decision totally," Mims said during a telephone interview yesterday afternoon. She said that she had been able to speak briefly with her son after the sentencing and she said, "He's glad that it's over."

In deciding what penalty Sails should receive, the jury, by law, had to consider whether various "mitigating" and "aggravating" factors existed in the case. If the jury had found that aggravating circumstances outweighed the others, they would have been obligated to send Sails to the gas chamber.

The jury found that Sails' crime was aggravated by the fact that the murder victim was a police officer attempting to do his job; that Sails shot the officer in an attempt to escape arrest, and that Sails committed the murder during an armed robbery.

But in Sails' favor, the jury acknowledged that he had no prior convictions for violent crimes; that his mental capabilities may have been somewhat impaired at the time of the crime, possibly by alcohol and drugs or by psychological factors; that he was unlikely to engage in further criminal acts; that he came from an unstable background; that he had never been jailed before, and that his previous crimes had not been of the "gratuitous or sadistic type."

State's Attorney Arthur A. Marshall Jr., who prosecuted the case, had called the killing "a cold-blooded execution" but the jury specifically found that the murder was not a "sadistic execution style" slaying.

Sails' defense lawyer, Michael Gallavan, said Sails was extremely nervous while the jury was out and he slept a great deal of that time.

"The more nervous he got, the more he'd sleep," Gallavan said.