Death penalty proponents in Congress have been trying to pass a federal capital punishment statute ever since the old ones were struck down by the Supreme Court in 1972. Bills have occasionally been reported out of committee, and last year a comprehensive death penalty bill was even passed by the Senate on a vote of 63-32. Fortunately, the House did not act.

Recent espionage and terrorist cases have given impetus to the drive to adopt this ultimate sanction, and the Senate Judiciary Committee is now marking up this year's version of a capital punishment bill. It would allow the death penalty for treason and espionage, federal crimes that result in the death of another person and, in some cases, attempts to kill the president of the United States. There are a number of reasons for questioning the breadth of the bill and challenging its constitutionality, but the Justice Department supports the measa majority of the committee will vote to send it to the floor.

This year, however, opponents have made some progress in limiting the bill's provisions. An amendment offered by Sen. Howard Metzenbaum (D-Ohio) has been adopted. It would prohibit the imposition of the death penalty on anyone who was under 18 at the time of the crime for which he was convicted. That sounds like a modest step, but it is not. Only six of the 38 states that allow execution have a similar age limitation. And six senators voted against the Metzenbaum proposal. Another group of amendments offered by Sen. Orrin Hatch (R-Utah) is designed to make the burden of proof more difficult at every stage of a death penalty case. Sen. Hatch favors the bill but seeks to make it more acceptable to those who question its constitutionality.

It is possible that a bill will be drafted that will be adopted and pass muster at the Supreme Court. A number of states have been able to craft these statutes. But even if such a bill is found to be constitutional, capital punishment will always be bad policy. It is encouraging that some whittling away is being done in the Judiciary Committee and that the bill will be a little bit better than its predecessors. But the core of the measure -- state-sanctioned killing -- is wrong and should be rejected. The courageous legislators are those who hold to this principle when cries for vengeance are rising.