A Navy panel deliberated for almost four hours today before deciding to spare the life of Mitchell T. Garraway Jr., a seaman from Suitland who was convicted of murdering his commanding officer.

Garraway, 22, was sentenced to life in prison and dishonorably discharged for the June 16 fatal stabbing of his superior officer, Lt. James Sterner. If the panel had chosen the death penalty, Petty Officer 3rd Class Garraway could have become the first Navy seaman to be executed since 1849.

Garraway's attorneys had contended that Garraway, who is black, was a victim of racism aboard the frigate USS Miller and stabbed his white commander out of frustration over continuing problems on the ship.

"I'm satisfied with the decision that was made today," Garraway said as he was led away in handcuffs and leg irons after the sentencing.

A Navy spokeswoman said Garraway will have to serve 15 years in prison before becoming eligible for parole.

Today's sentencing decision was made by the same court-martial panel of eight men -- three of them black -- that convicted Garraway of premeditated murder Jan. 30. Garraway added today that he is "very unsatisfied with the decision they made on the premeditation conviction . I think we can appeal it. Of course the military's not going to be fair."

While pleased that Garraway escaped the death penalty, both his civilian attorney, Trevor L. Brooks, and his mother, Mattie Umrani of Suitland, also were unhappy with the final outcome of the trial. Brooks had urged the panel to reconsider its conviction for premeditated murder in favor of a lesser charge of unpremeditated murder.

"It's hard to be happy when somebody's going to spend their life in jail," Brooks said, "but under the circumstances all we can do is aggressively pursue the appeal of the conviction."

Navy prosecutor Daniel E. O'Toole, who had vigorously pressed for the death penalty, would comment only that he had "represented the interest of the U.S. Navy to the best of my ability."

O'Toole had told the panel in his final argument today that the killing of Lt. Sterner "caused a rift in the . . . discipline of the Navy."

"If you are morally outraged by his act of violence . . . most important, if you are troubled by the impact on the good order and discipline of the Navy, you must render a sentence of death. And may God have mercy on his soul," O'Toole said.

Sterner, 35, a former Prince William County teacher, bled to death in a passageway of the frigate while on a training cruise near Bermuda. He had been stabbed twice in the back with a Marine combat knife.

In his closing arguments, defense attorney Brooks described Garraway as "a person with immature development, a sensitivity to racism that's above normal, a person who cannot express himself."

He said that Garraway's stepfather, whom he described as a Vietnam veteran and "a child of the '60s," instilled a radical pride in the young Garraway: "Don't back down from racism. Don't back down from the white man."

When Garraway joined the Navy at 18 after dropping out of Suitland High School, he encountered racism, Brooks said, and was unable to cope with the pressures.

"Mitch had a chip on his shoulder," Brooks said, "a chip produced by his stepfather, a chip produced by the poverty of his childhood. When he entered into the Navy, it was a dangerous mix. The Navy is a confining place. If you and certain people don't get along, tough cookie."

Testifying in his own behalf Thursday, however, Garraway placed the blame for his problems not on Sterner but on a petty officer who was his direct supervisor in the engineering department and who, he said, frequently made racist remarks. He said that he had never planned to harm Sterner and that he "just snapped" when he stabbed Sterner in the ship's corridor.

A seaman testified, however, that Garraway was upset about a denied promotion and told him he was going to "kill Sterner."

Prosecutor O'Toole, in his rebuttal, said that "the evidence simply doesn't support that Sterner or anybody else on the ship was racist."