Last month's sniper slayings may have given a temporary boost to support for the death penalty, but long-term public opinion on the issue has remained relatively unchanged, experts on both sides of the debate say.

Seventy percent of Americans surveyed during the height of three weeks of sniper terror that riveted national attention said they support the death penalty, according to the Gallup Organization.

That is statistically similar to the number who favored execution in polls conducted in May 2001 -- before the 911 terrorist attacks -- and in May 2002, when support ranged from 67 to 72 percent, George H. Gallup Jr. said in a written report.

"Survey data suggest recent events have had little effect" on the public's opinion about execution, Gallup said.

"What that tells us is Americans are able to distinguish between individual tragedies and overall public policy," said David Elliot, director of communications for the National Coalition to Abolish the Death Penalty.

The Oct. 24 arrest of two drifters, John Allen Muhammad, 41, and John Lee Malvo, 17, in the sniper shootings triggered a public tug of war among prosecutors in Virginia and Maryland over who should bring the first prosecution. A principal issue in the debate was who was most likely to obtain the death penalty upon conviction.

U.S. Attorney General John D. Ashcroft made clear that a key motivation in his decision to send the suspects to Virginia for trial was that "the ultimate sanction be available." Muhammad and Malvo have been linked by police to shootings that left 10 people dead and six wounded in the Washington area. They also have been tied to five other shootings, four of them fatal, in other states.

The killings came at a time when support for the death penalty among Americans appeared to be eroding, the number of executions was declining and state legislatures nationwide were debating, limiting or ending the practice, death penalty opponents said.

"Two thousand and one was the first year in modern history that we were on the offensive instead of defensive," said Elliot of the National Coalition to Abolish the Death Penalty. "In almost every death penalty state, death penalty reform legislation was debated, and we didn't see any state expand the death penalty substantially."

Maryland Gov. Parris N. Glendening declared the nation's second moratorium on executions this spring, when he faced the prospect of the state putting to death five men, four of them blacks convicted of killing whites, before he leaves office in January.

University of Maryland criminologists are conducting a study, scheduled for completion in December, of whether the state's system of capital punishment is affected by racial bias.

Illinois also has instituted a moratorium -- fearing that its capital punishment system is so flawed that innocent people might be executed. Last month, state officials heard more than 140 clemency petitions from inmates on death row.

Richard A. Devine, the state's attorney of Cook County -- which encompasses Chicago and its suburbs -- said Thursday that the hearings often served to recount the coldblooded nature of the crimes and the continuing anguish of the victims' families.

"It brought home again why we do have a death penalty," said Devine, who supports execution. "You see the pain of the victims.

"That was true also with the sniper slayings," he said. "They were so public, so visible and so without any kind of motive, except to kill, that I think it starkly brought forward to people just how bad some things can be.

"Here, allegedly, we have two people who stalked and identified individuals for the purpose of killing them, for no other purpose," he said. "When you see that cold-blooded inhumanity to man, it brings us back to the sad fact that we need severe punishments."

Devine said such crimes reinforce in the minds of death penalty supporters why the punishment is needed and may influence those who are "on the bubble" about the issue. He said such crimes probably do not influence those who are strongly opposed.

Public opinion on the issue is malleable and has swung widely in the decades since pollsters have tracked it, from a low of 42 percent who favored execution in 1966 to a high of 80 percent in 1994, surveys show.

Support tends to increase when the overall rate of violent crime is high, some experts said -- not, in most cases, in response to any single crime, no matter how heinous.

Locally, the sniper case might have influenced this month's gubernatorial election in Maryland, according to William G. Otis, a former Justice Department prosecutor and adjunct law professor at George Mason University.

Republican Robert L. Ehrlich Jr. promised voters he would end Glendening's moratorium on executions -- and he reiterated that vow Friday, as he announced preparations for taking over the governor's office in January.

"The sniper had a considerable impact on people," Otis said last week. "There was a fearfulness, a kind of an apprehension of an attack from nowhere that people felt while the sniper was still on the loose.

"I think it figured into the election results in Maryland," he said. And if Ehrlich ends Maryland's moratorium on executions, then "exactly one-half of the moratoriums in this country will go bye-bye, to my way of thinking, as a direct result of this sniper.

"There are some things that a civilized country actually should not tolerate," he said "and this sniper is one of them."