Charter schools are the most popular alternative to traditional public schooling in the United States. The majority of research indicates positive effects of charter schools on student performance in traditional public schools. Most studies use the share of charter school students enrolled as a measure of the competitive pressure of charter schools. We contend that competitive pressure on traditional public schools also comes from an alternative teaching environment provided by charter schools. A teacher may be attracted to the freedom that a charter school provides, which can empower them to be innovative. These changes can spill over to traditional public schools. We empirically examine the impact this choice for teachers has on student performance in traditional public schools. We measure student performance by the percentage of 8th-grade students that attain proficiency level and above on National Assessment of Educational Progress exams. Our results indicate a positive relationship between teacher freedom in charter schools and the performance of traditional public school students.