This study reports theory-testing laboratory experiments on the effect of yardstick competition on corruption. On the incumbent side, yardstick competition acts as a corruption-taming mechanism if the incumbent politician is female. On the voter side, voters focus on the difference between the tax rate in their own jurisdiction and that in another. If the tax rate is deemed unfair compared to the one in another jurisdiction, voters re-elect less. The findings support the claim by Besley and Case (1995) that incumbent behavior and tax setting are tied together through the nexus of yardstick competition. This renders generalizability to these laboratory experiments and addresses some concerns raised by Levitt and List (2007).