President Obama has ordered the Department of Health and Human Services to craft new rules that would facilitate hospital visitation rights for same-sex couples and smooth the way for gays and lesbians to make medical decisions on behalf of their partners.

On public policy grounds, the president’s directive is indeed welcome. Two people who have joined in a long-term, committed, and mutually reinforcing relationship are entitled to equal treatment, regardless of sexual preference.

Regrettably, however, the president has exceeded his constitutional authority. His order to his health secretary is deficient in two respects:

First, the government is invoking its power to spend for Medicare and Medicaid, then demanding that all hospitals receiving such funds adopt the new rules. But there is no explicit power to spend in the Constitution. Despite the Supreme Court’s contrary pronouncements, spending is permitted only as a “necessary and proper” means to execute other enumerated powers. Quixotic though it might sound given post-New Deal jurisprudence, there is no enumerated power for the federal government to be engaged in providing health care to private citizens.

Second, the Constitution requires that “All legislative Powers … shall be vested in a Congress.” That means laws conferring benefits or imposing obligations on private parties are supposed to be passed by the legislature, not the executive. Yes, the Court has condoned delegations of legislative authority for a vast array of programs, but that merely reinforces the need to interpret the Constitution as it was originally understood.