Diesel in Chile receives a different tax treatment depending on its use. If diesel is used in
industrial activities the diesel tax paid can be used as a credit against VAT and if diesel is
used in freight or public transportation (basically trucks and buses) a fraction of gasoline
taxes paid can be used as a credit against VAT. As a result of this different tax treatment
firms have incentives to use “tax exempted” diesel in activities requiring “non tax exempted”
diesel. This price wedge generates and opportunity for tax evasion. In this paper we analyze
the impact of a tax enforcement program implemented by the Chilean IRS, where letters
requiring information about diesel tax credits were sent to around 200 firms in 2003. Using
different empirical strategies to consider the non-randomness of the selection of firms, we
find that firms receiving a letter decreased their diesel tax credits by 16%.