The Trump administration on Thursday issued advice to states that will allow them to subvert and diminish a key provision of Barack Obama’s Affordable Care Act, according to a report from The Washington Post. Under ACA regulations, federal insurance subsidies could only be used to help lower- and middle-income Americans buy insurance plans from marketplaces created by the landmark law. These plans all met a standard of minimum care. But under Trump’s new advice, also known as “waiver concepts,” states can use those subsidies to fund enrollment in plans that aren’t in the ACA marketplace—including lower-quality plans promoted by his administration. What’s worse, the advice would also allow states to let consumers who already have coverage through their employer use those federal funds to pay off premiums or other medical expenses. The advice does not, however, allow states to charge more for patients with pre-existing conditions, which has proven to be one of the most contentious points of the health-care debate. The Post notes that the legality of the waiver concepts are already up for debate: An analysis from the Brookings Institution noted that “there are serious questions” about whether the advice is legally sound.