John M. Poindexter was sentenced to six months in prison yesterday by a federal judge who said the one-time national security adviser to former president Ronald Reagan was "the decision-making head" of a scheme to deceive Congress in the Iran-contra affair and to "invalidate the decisions made by elected officials."

Poindexter, 53, a retired Navy rear admiral and the highest-ranking Reagan administration official brought to trial in the Iran-contra affair, showed no emotion and maintained his silence.

When U.S. District Judge Harold H. Greene asked Poindexter if he had anything to say before the sentence was handed down, the former career Navy officer rose to his feet and said, "Your honor, I don't have any comment."

His only visible reaction was to smile at his lawyers after the sentence was pronounced and to kiss his wife, Linda.

Poindexter became the first person convicted in the biggest scandal of the Reagan presidency to receive a prison term. He had faced a maximum of 25 years in prison and a $1.25 million fine.

After the court session, defense attorney Richard W. Beckler said Poindexter will appeal his conviction on five felony charges that he deceived Congress about the White House's role in a politically embarrassing 1985 arms transfer to Iran and in supporting the Nicaraguan contras during a two-year congressional ban on aid to the rebels.

If his appeals are unsuccessful and he is imprisoned, Poindexter will serve about five months of his sentence, federal prison officials said yesterday.

Greene imposed no fine or other conditions, saying a fine would be a "crush- ing burden" on Poindexter and his family, particularly in view of his "large legal


Navy spokesmen have said that Poindexter's pension, which is about $55,000 a year, will not be affected by his conviction.

Six others previously convicted in the Iran-contra affair, including former national security adviser Robert C. McFarlane and former National Security Council aide Oliver L. North, were spared prison sentences.

McFarlane and North were fined and ordered to perform community service.

Outside the courthouse after the sentencing, Poindexter and his wife thanked a group of supporters, who carried placards including one that said "God Bless Admiral Poindexter, He Stood Up for Freedom" and another that read "Read our lips -- Pardon Now."

Beckler, Poindexter's chief lawyer, asked Greene not to imprison the 33-year Navy veteran, whom Beckler described as an "honorable man" who has already "suffered enough." Poindexter resigned as national security adviser when the scandal erupted in late 1986.

But Greene said that sparing Poindexter a prison sentence "would be tantamount to a statement that a scheme to lie to and obstruct Congress is of no great moment" and would "encourage others in positions of authority and secrecy to frustrate laws that fail to accord with their notions of what is best for the country, and to carry out their own private policies in the name of the United States."

Poindexter spared Reagan major political embarrassment and possible legal difficulties when he told the congressional Iran-contra panels in July 1987 that he did not inform Reagan of a central issue of the scandal -- the decision to divert profits from the secret U.S. -- Iranian arms sales to support the contras.

"The buck stops here with me," Poindexter said in 1987.

On April 7 a U.S. District Court jury convicted Poindexter on all five felony counts lodged against him, including conspiracy and obstructing and lying to Congress. The verdict provided Independent Counsel Lawrence E. Walsh with his most sweeping victory.

In a brief statement after the sentencing, Walsh said he was "pleased" that Greene "weighed" his request to imprison Poindexter.

Dan K. Webb, the chief Poindexter prosecutor, said in court that "John Poindexter is the superior. He has to be held accountable."

Both Webb and Greene noted that Poindexter also has expressed no remorse.

Greene also warned of the dangers of high government officials using national security concerns to mask deceit and wrongdoing.

Greene said the government must maintain secrets, but "if members of the security apparatus could, with impunity, keep from those elected by the people that which they're entitled to know -- or worse, feed them false information -- those who control the classified data could be the real decision makers. That is precisely what happened here."

"With all due respect to the distinguished military records of Adm. Poindexter, Col. North . . . and the others," Greene said, "they have no standing in a democratic society to invalidate the decisions made by elected officials."

Greene said he decided not to give Poindexter a stiffer sentence because of his military career and because "his culpability does not differ so greatly from that of the other Iran-contra figures."

Sources have said that Walsh is considering summoning Poindexter to testify before a new federal grand jury whose work includes examining whether other Reagan administration officials not previously charged lied to Congress. North has already appeared before the grand jury twice.

Carl R. "Spitz" Channell: The conservative fund-raiser pleaded guilty April 29, 1987, to using his non-profit National Endowment for the Preservation of Liberty to raise more than $2 million to arm the Nicaraguan contras. Sentenced to two years' probation and a $50 court fee for tax fraud, Channell died May 7 from injuries received when he was hit by an auto.

Richard R. Miller: The head of a Washington public relations firm that promoted the contras' cause pleaded guilty in federal court May 6, 1987, to conspiring to supply them with military equipment bought with tax-deductible contributions. He was sentenced to two years' probation for tax fraud conspiracy.

Robert C. McFarlane: The one-time national security adviser to former president Ronald Reagan pleaded guilty March 11, 1988, to four misdemeanor charges that he withheld information from Congress about the Reagan administration's secret aid to the contras during a two-year period when Congress had restricted U.S. military assistance to the rebels. He was sentenced to two years' probation, 200 hours of community service and fined $20,000.

Oliver L. North: The now-retired Marine lieutenant colonel and former Reagan White House National Security Council staff aide was convicted May 4, 1989, of obstructing Congress, unlawfully mutilating government documents and taking an illegal gratuity. U.S. District Judge Gerhard A. Gesell fined North $150,000 and gave him a three-year suspended sentence and two years' probation. North was also disqualified from holding federal office and ordered to perform 1,200 hours of community service.

Richard V. Secord: The retired Air Force major general pleaded guilty Nov. 8 to lying to congressional investigators when he denied knowing that North had benefited form Iran-contra sale profits. He was sentenced to two years' probation.

Albert Hakim: The businessman pleaded guilty Nov. 21 to a misdemeanor charge of helping to supplement North's government salary by arranging to pay for a security system at North's home. Gesell placed Hakim on two years' probation and fined him $5,000. Hakim also removed his claim to $7.3 million from the secret arms sales now frozen in Swiss bank accounts.