With the recent U.S. Supreme Court term now concluded, we have reflected on the major role state attorneys general have played in defending state governments against federal encroachment. This recent activism yielded significant victories for the idea that federal power has limits and that dual sovereignty means something.

State attorneys general have expanded their responsibilities for protecting state citizens since the early 1990s when they targeted major tobacco companies for inflicting harm on the public and state treasuries alike. Ever since the national tobacco settlement, citizens have expected their attorneys general to play a more active, creative role in protecting the public interest. Beyond our more traditional consumer-protection efforts, we have cracked down on telemarketers, pursued pharmaceutical giants for fraudulent marketing, brought accountability to nonprofits and prosecuted public corruption.

Now we see attorneys general focusing their efforts in a new and important direction: toward the defense of federalism, in which states as sovereign entities and the federal government share governing power.

First, attorneys general defend federalism by protecting state actions from federal intrusion. In Indiana, the Legislature passed a law prohibiting abortion providers from also being Medicaid providers, to prevent indirectly subsidizing abortion procedures with tax dollars. The federal government, however, has refused to allow Indiana to operate Medicaid this way, and our office is defending Indiana’s prerogative to manage our Medicaid dollars according to our state’s statute, not the dictates of Washington bureaucrats.

In Indiana and other states, attorneys general also defend state laws concerning illegal immigration and voter identification from intrusion by the U.S. Department of Justice.

Second, attorneys general protect states from unprecedented expansion of federal authority. The EPA has imposed stringent regulations of carbon dioxide emissions that potentially could restrict economic growth without producing any real environmental gains. State AGs frequently unite to challenge these ill-considered, possibly unlawful EPA rules that would cut energy production, raise consumer rates and eliminate jobs.

The Indiana Attorney General’s Office joined 25 other states challenging the Affordable Care Act, commonly known as “Obamacare.” We joined the challenge because we believed the health care law as written presents a grave threat to state budgets, people’s wallets and liberty in general. The individual mandate is an unprecedented expansion of federal power that alters the relationship between citizens and the federal government, with a direct, negative effect on individual liberty. Although the U.S. Supreme Court refused to strike down the individual mandate by labeling it a tax, in the process the Court confirmed important limits on congressional power – a decision state AGs were instrumental in bringing about.

The federal health care law’s Medicaid expansion would have forced cash-strapped states to choose whether to shell out billions of new dollars for a greatly expanded entitlement or lose Medicaid funding. States achieved a great victory when the Supreme Court ruled the federal government cannot coerce states in this way. Now states can make their own decisions whether to expand their Medicaid programs without the threat of a federal cutoff of all Medicaid if they decline.

Without the commitment of state attorneys general, the federal government could run roughshod over federalism. By joining the lawsuit against the federal health care law, challenging EPA’s overregulation of the American economy and defending our state’s laws from federal preemption, the Indiana Attorney General’s Office has been policing the boundary lines of dual sovereignty intended by our Founders, and protecting individual liberty in the process.