The judge who threw out Maryland’s Wal-Mart law (which would have required large employers to dedicate at least 8 percent of its Maryland employee compensation to health care benefits) apparently did so on interstate commerce grounds:

In yesterday’s decision, Judge J. Frederick Motz of Federal District Court ruled that the Maryland law, which was overwhelmingly passed by the Democrat-controlled state legislature in January, was pre-empted by the federal Employee Retirement Income Security Act, or Erisa.

The act sets out a national standard for company benefit plans, replacing what would otherwise be a patchwork of state regulations.

The law “violates Erisa’s fundamental purpose of permitting multistate employers to maintain nationwide health and welfare plans, providing uniform nationwide benefits and permitting uniform national administration,” he wrote in the decision.

Maybe that same judge should throw out state health insurance mandates. They have the effect of making it impossible for private health insurance companies to engage in interstate commerce. Once upon a time, the right to engage in interstate commerce free of state regulation was something in the Constitution — it did not merely depend on Erisa.