Vermont Attorney General T.J. Donovan has settled a fraud investigation over the billing practices of Jonathan Gruber, one of the architects of Obamacare who was advising the state over its a now-abandoned single-payer plan.

Under his $450,000 contract with the state, Gruber was supposed to submit monthly invoices describing the work he did and how much he was billing for his work. The attorney general’s office said Gruber filed at least two invoices that were false that pertained to work performed by a research assistant who was working for him.