Boston — Fewer and fewer Americans are without an opinion on the emotion-charged issue of capital punishment for convicted murderers. Death penalty supporters outnumber opponents better than 2 to 1, according to polls taken within the past several months by the Gallup and Louis Harris organizations.
The Harris survey in January, a few weeks after the lethal injection execution of a convicted slayer in Texas, found that 68 percent of those queried support capital punishment and 27 percent oppose it, with the remaining 5 percent ''undecided.'' Twice as many were recorded in the undecided category a decade ago when death penalty proponents topped the opponents 59 percent to 31 percent.
Death penalty foes are not about to give up their battle, despite the recent Harris poll indicating that hardly more than 1 in 4 share their view on what has become an increasingly volatile issue.
Larry Cox, deputy director of the US branch of Amnesty International, makes this clear. He says that while his organization's stance will remain firm, its leaders now must ''rethink our strategies.''
He hints that this might include a more concerted effort to rally members of the clergy and others to fight what he fears may be a sharp increase in the number of executions in the United States.
While unwilling to speculate what impact it might have, death penalty abolitionists were pleased by the condemnation of capital punishment by Pope John Paul II, the first pontiff in history to take such a stand. In a mid-January speech to the Vatican diplomatic corps, the head of the Roman Catholic Church called on world governments to grant clemency or pardon prisoners on death row.
More recently, Supreme Court Justice Lewis F. Powell Jr. called for a thorough rethinking of capital punishment in the US. He pointed to the drawn-out appeal process in capital cases as a reason for either streamlining the process or abolishing the death penalty altogether. He said that current procedures, which allow for multiple appeals, represent a ''malfunctioning of our system of justice.''
Leaders of Amnesty International, who oppose capital punishment largely on moral grounds, note that it is outlawed in many countries, especially in the Western Hemisphere. Six nations, including France, which threw out the guillotine in late 1981, have wiped the death penalty off their books during the past seven years.
Mr. Cox, terming the April 22 killing of John Louis Evans III in the Alabama electric chair as ''grotesque,'' says he was surprised the much-publicized execution, which succeeded only on the third try, caused ''little public outrage.''
Death penalty critics throughout the US, like Henry Schwarzchild of the American Civil Liberties Union, hold there is ''no such thing as a humane execution.'' They concede, however, that some methods may appear less violent and thus perhaps more acceptable to the public.
Mr. Schwarzchild notes that within the past year at least four states - Arkansas, Massachusetts, Montana, and Washington - have provided for lethal injection either as an alternative to or replacement for other forms of execution.
A similar measure, strongly backed by Gov. Thomas H. Kean, is moving through the New Jersey Legislature. In several other capital punishment states, including Alabama, proposals for executions through lethal injections are being pushed.
Jack Boger of the NAACP Legal Defense and Educational Fund cites the Evans case, the seventh execution since the death penalty was reinstated in the US in 1976 and the third within the past nine months, as ''part of a rising tide.''
He notes that last July Benjamin Renshaw, acting director of the Federal Bureau of Justice Statistics, forecast as many as three executions a week this year. This would be due to the fast-climbing number of inmates on death rows around the US, he observed.
While this has not happened, Messrs. Boger and Schwarzchild warn that ''executions in substantial numbers are imminent,'' with many condemned prisoners nearing the end of the appeal process. To what extent the death penalty pace quickens, and how soon, could hinge in part on the outcome of a case argued earlier this spring before the US Supreme Court.
The dispute is whether a federal appeals court must grant a stay of execution to condemned convicts whose habeas corpus appeals are still unresolved, but who are unable to show that they are raising a substantial, new issue.
The high court decision could have particular impact on some 225 prisoners under death penalty sentences in Louisiana, Mississippi, and Texas, according to Boger.
As of April 20, his organization's tally of death-row inmates, including the US military and a half dozen of the now 38 capital punishment states, stood at 1 ,168. This is nearly a 38 percent increase over the past 20 months.
The current condemned population includes 1,156 males and 12 females. It is 42 percent white, 42 percent black, 4.7 percent Hispanic, with the remaining 1.3 percent native American, Asian, and others.
Florida (with 195), Texas (151), and California (124) have the most inmates with death sentences. In the latter state, the number is four and a half times greater than three years ago.
Efforts to expand New York State's capital punishment law, which now covers only those prison inmates convicted of killing a corrections employee, failed March 10 when Gov. Mario Cuomo vetoed a legislature-approved measure. As a substitute he filed a bill providing life imprisonment, without parole or pardon , for convicted first-degree murderers.
At least two other states - Alaska and Oregon - have been considering or are expected to take up capital punishment proposals this year. In Michigan, a move is expected early next year to put the death penalty question on the November 1984 ballot. A similar move there last year fell through when the initiative petition lacked enough signatures to qualify for voter consideration.
In Massachusetts, where a state constitutional amendment allowing capital punishment breezed through on the November 1982 ballot, legislation providing for such executions for slayings involving certain types of crime was enacted in December and signed into law by former Gov. Edward J. King.
Democratic state Rep. Michael F. Flaherty, an outspoken booster of reinstatement of capital punishment in Massachusetts, says that ''having this penalty on the books will make murderers think twice before they kill. It is a warning that if you take a life, your life will be in jeopardy.
While the US military and all but 12 states - Alaska, Hawaii, Iowa, Kansas, Maine, Michigan, Minnesota, North Dakota, Oregon, Rhode Island, West Virginia, and Wisconsin - have death penalty laws on their books, the federal government, outside of the armed forces, provides it only for slayers during a plane hijacking.
US Sen. Strom Thurmond (R) of South Carolina wants to considerably expand this to include a variety of illegal acts such as treason, espionage, and attempting to kill a President.
Similar legislation made it out of his Senate Judiciary Committee in 1981 but languished on the Senate calendar for the rest of the 97th Congress.
Provisions for a federal death penalty are embraced in the Reagan administration's legislation for a Comprehensive Crime Control Act, filed in mid-March. Do Americans favor capital punishment?
Yes No Undecided 1965 38% 47% 15% 1969 48% 38% 14% 1970 47% 42% 11% 1973 59% 31% 10% 1976 67% 25% 8% 1983 68% 27% 5% Source: Harris Poll