The Boston Marathon bomber’s case poses a question without an answer.

The U.S. Supreme Court last week held what can only be described as odd oral arguments in the case of the surviving Boston Marathon bomber.

“Odd” is an odd word to use to describe the sterling legal arguments. But new Justice Amy Coney Barrett suggested it when she asked government lawyer Eric Feagin what the point was of the proceeding.

“I’m wondering what the government’s endgame is here,” she said, admitting difficulty “following the (government’s) point.”

Her confusion relates to the government’s schizophrenic approach to the punishment of

Dzhokar Tsarnaev.

The government is asking the high court to reinstate a jury-ordered death penalty that was overturned by a federal appeals court. But at the same time President Joe Biden’s Justice Department seeks death in the courts for Tsarnaev, Attorney General Merrick Garland has suspended executions of federal inmates facing the death penalty.

“So the government has declared a moratorium on executions, but you’re here defending his death sentence. … And if you win, presumably that means that he is relegated to living under threat of a death penalty that the government doesn’t plan to carry out,” Barrett stated.

Feagin essentially told Barrett that the issue before the court is the validity of the appellate court decision, and how the executive branch proceeds in the future regarding death cases is a separate, non-justiciable issue. He would be correct in his analysis, but the government lawyer’s bobbing and weaving demonstrates the conflicted nationwide debate over the propriety of capital punishment.

Some states have it, and other states, including Illinois, do not. Congress passed a federal death-penalty law that applies in the worst kinds of cases — the Boston Marathon bombing is one; the 2017 kidnapping and murder of a University of Illinois student from China is another.

But even if jurors are persuaded that death is appropriate — they were in the bombing case but not the kidnapping/murder case — the Biden administration rejects executions on moral grounds. At the same time, some judges — in both the state and federal courts — refuse to uphold death-penalty sentences because of personal opposition they disguise with unpersuasive legalities. The appeals court ruling in Tsarnaev’s case is just one example.

That’s not the only hitch in the death-penalty debate. Opponents argue that it is cruel, that government ought not be in the business of executing criminals no matter what they do because it cheapens human life. Instead, they suggest life in prison as an alternative. But which is more harsh?

Tsarnaev was 19 when he and his brother planted the bombs that destroyed and devastated so many lives. Now he’s 27 and held at the federal super-maximum security prison in Florence, Colo. The best he can look forward to is one day after another in the same cold surroundings until his life expires.

Tsarnaev may have been filled with jihadist zeal when he set out on his murderous mission. But how does he feel now about the importance of what he did, and how, if he is spared execution, will he feel 20 years from now when he reflects on what his life might have been?

Sirhan Sirhan, who was 24 when he assassinated presidential candidate Robert Kennedy in 1968, has been miserable behind bars. Even at 77 — 53 years later — he’s desperately seeking freedom for the balance of his life.

Tsarnaev deserves the harshest possible punishment for his crucial role in his horrible crime.

But what is that? The Supreme Court will address the legal question, and the Biden administration will continue to exercise its administrative prerogatives.

Whatever happens, the only way Tsarnaev should or will ever leave federal custody is in a box.