http://www.epi.org/publications/entry/6759/

data indicates that state and local government employees in Wisconsin are not overpaid. Comparisons controlling for education, experience, organizational size, gender, race, ethnicity, citizenship, and disability reveal that employees of both state and local governments in Wisconsin earn less than comparable private sector employees. On an annual basis, full-time state and local government employees in Wisconsin are undercompensated by 8.2% compared with otherwise similar private sector workers. This compensation disadvantage is smaller but still significant when hours worked are factored in. Full-time public employees work fewer annual hours, particularly employees with bachelor’s, master’s, and professional degrees (because many are teachers or university professors).
When comparisons are made controlling for the difference in annual hours worked, full-time state and local government employees are undercompensated by 4.8%, compared with otherwise similar private sector workers. To summarize, our study shows that Wisconsin public employees earn 4.8% less in total compensation per hour than comparable full-time employees in Wisconsin’s private sector.