Legal tradition says that hard cases make bad law. Few cases are harder than those having to do with the plight of the families of 9/11 victims.

This led Congress to adopt the Justice Against Sponsors of Terrorism Act. Jasta, as it is known, gives federal courts the power to determine whether a foreign state has intentionally sponsored terror against American citizens. This power, however, belongs to the president and cannot be constitutionally wielded by the judiciary.

Jasta was enacted in September over President Obama’s veto. Although the law mentions no particular state, its target is clearly Saudi Arabia. The families of 9/11 victims have long sought money damages from the kingdom, based on the Saudi citizenship of most of the 9/11 attackers and planners.

A federal judge’s determination that Saudi Arabia intended to sponsor the 9/11 attacks would greatly strain U.S.-Saudi relations. More generally, whether the U.S. should identify any particular state as a terrorism sponsor is a supremely sensitive foreign-policy decision, involving myriad factors and rendering impossible U.S. cooperation with such a state.

For this reason, the Constitution reserves such determinations to the political branches of government, and more particularly to the president, who is principally responsible for the formulation and implementation of American foreign policy.

If a president decides to classify a nation as a sponsor of terrorism, Congress can define the consequences, including depriving such states of the sovereign immunity from lawsuit that they ordinarily enjoy in U.S. courts. It cannot, however, force a president to make such a determination. Nor can Congress vest such decision-making authority in the courts.

The Supreme Court’s ruling last year in Zivotofsky v. Kerry is instructive here. The court struck down Congress’s effort to require the executive branch to recognize Jerusalem as part of Israel by permitting American citizens born there to have their passports indicate “Israel” as their birthplace. It said, “these matters are committed to the Legislature and the Executive, not the Judiciary.”

The judiciary doesn’t have access to the sort of information that would enable it to determine the motives of a foreign state. And even if it did, deciding whether to classify a country as a sponsor of terrorism is a task inherently ill-suited for judicial discernment. Recognizing and acting upon such information lies at the very core of the president’s foreign-affairs powers.

Jasta’s enactment has already damaged U.S.-Saudi relations and has alarmed many traditional U.S. allies, who understandably do not like the outsourcing of sensitive foreign-policy issues to the American judiciary and private litigants. Jasta is unconstitutional and should be struck down as such.

Messrs. Rivkin and Casey practice appellate and constitutional law in Washington, D.C.

Source: http://www.wsj.com/articles/hold-on-jasta-minute-1480551317