Twice in two days, the U.S. Supreme Court’s conservative supermajority has issued sweeping rulings that cut against established precedents and will hamstring the ability of regulatory agencies to impose rules on powerful business interests.

On Friday, the six Republican-appointed justices overturned a 40-year-old foundational part of administrative law, the Chevron doctrine, which will make it easier to successfully challenge regulations in court by eliminating a requirement that courts defer to the expertise of federal agencies in interpreting their laws.

The day before, the justices had struck down a key practice used by many agencies to enforce rules via in-house tribunals, rather than suing accused malefactors in federal court before juries.