The Queens district attorney, Richard Brown, is single-handedly reviving the prospects of the death penalty in New York.

In a brief recently filed with the state’s highest court, Mr. Brown’s office urges the Court of Appeals to allow prosecutors across the state to resume seeking death sentences.

The brief calls on the court, which sits in Albany, to limit the scope of a landmark 2004 decision that struck down the state’s death penalty on a technical basis. That decision helped to empty out the state’s death row of all but one convict, John Taylor, whose execution Mr. Brown still seeks. For death penalty advocates, Taylor’s appeal is emerging as a last opportunity to convince the courts to reinstate capital punishment in New York.

The Taylor case highlights the uncertain position capital punishment occupies in New York politics. With the Legislature showing no serious willingness to fix the current death penalty statute in response to the court’s earlier decision, and with no state capital cases on the horizon, the death penalty could disappear entirely as a political issue in New York if the court overturns Taylor’s death sentence.

Or, as some death penalty advocates suggest, the death penalty dispute is as politically potent as ever, and is simply on hold as advocates and opponents wait to see how the court will rule on Taylor’s appeal.

Either way, the case is emerging as a watershed event in the history of the death penalty in this state. For their part, the Queens prosecutors are demanding that the court use the case to issue a broad edict on the death sentence.

“This is not an issue that can be addressed in a future case, or an error that can be corrected another time,” the brief reads. “This issue can never again present itself: Taylor is the last existing capital case.”

In the 2004 case, the Court of Appeals overturned the death sentence of Stephen LaValle, reasoning that the jury instructions required by law were coercive. Those instructions inform a jury that if it deadlocks on the question of death or life in prison, the judge will impose a sentence. The court ruled that the possibility a judge’s sentence would allow for the possibility of parole could improperly coerce a juror to vote for death in order to prevent a deadlock.

The makeup of the court has dramatically changed since it issued the decision in 2004, and some court observers say it is possible the court will overturn its precedent.

“New York’s death penalty statute is constitutional, both on its face, and as applied to defendant in this case,” Mr. Brown argues in the brief.

But the brief’s main argument, one that Mr. Brown has signaled he will make, says the court could uphold the execution of Taylor without reversing the 2004 decision.

That possibility, the brief argues, derives out of a grim fact: the number of murders for which Taylor is responsible.

Taylor orchestrated the murder of five employees at a Wendy’s restaurant in Flushing. Because of the multitude of victims, the judge in that case, Steven Fisher, told the jury that he would “almost certainly” sentence Taylor to consecutive terms totaling 175 years if the jury deadlocked.

Instructions such as these, the brief argues, leave no room for a juror to believe that a convict could ever be paroled. Mr. Brown is urging the court to limit the LaValle decision to apply only to single murders or instances in which a judge is unable to state with certainty that parole is an impossibility.

The effect of such a decision would be, in effect, to reactivate the death penalty in New York.

In cases involving multiple victims, Queens prosecutors say, all a judge would need to do to avoid the pitfalls of the current death sentence law would be to inform the jury that he would sentence the defendant to consecutive life sentences in the event of a deadlock.

Those instructions “would completely remedy the constitutional concern of a coerced death verdict expressed by the LaValle majority,” the brief said.

For his demand that Taylor be executed, Mr. Brown is facing criticism from death penalty opponents who say he should stick with prosecuting cases, not deciding the appropriate punishments, a task better belonging to the Legislature.

“The DA is saying, I don’t need courts or the Legislature to authorize capital punishment — as long as I have a theory in my head, I can pursue it,” an opponent of the death penalty, Bryan Stevenson, a professor at New York University’s School of Law, said. “I think it’s a problem for a prosecutor to unilaterally make a determination of the law, when the courts have made a definitive judgment that the statute is unconstitutional and the Legislature has also made a deliberative determination not to reenact a functioning death penalty.”

Mr. Brown has an entirely different interpretation on the significance of the Legislature’s silence on the subject of the death penalty following the 2004 decision.

“If the populace or the Legislature is as opposed to capital punishment as defendant contends, than the burden falls upon them to rescind the statute,” his brief says.

The case is not yet set for argument.