Royce was the first and still only woman to be granted an FIA International Chief Scrutineer License for Formula 1. Her service was exemplary in length and quality. Her 35-year career as a Chief Scrutineer spanned a full 50% of the history of F1 as an international series. In November 2020, she was recognized as the Best Chief Scrutineer of 2020 by the FIA. Since 2012, she also served as Chief Scrutineer for all individual FIA events in the United States as well as MotoGP for FIM. This includes World Endurance Championship (WEC), Formula E, and World Rallycross (World RX). Royce began her scrutineering career with the Detroit Region SCCA in 1972 and was named chief scrutineer for a regional race in 1976. She first volunteered as a scrutineer for F1 when the series came to Detroit in 1982. She was named co-Chief Scrutineer in 1985 before becoming sole scrutineer a year later. In 2012, Royce co-authored the book Learn & Compete: A Primer for Formula SAE, Formula Student, and Formula Hybrid Teams.