Economic growth with constraints on tax revenues and public debt

"This paper evaluates optimal public investment and fiscal policy for countries characterized by limited tax and debt capacities. We study a non stochastic CRS endogenous growth model where public expenditure is an input in the production process, in countries where distortions and limited enforceability result in limited fiscal capacities, as captured by a maximal effective tax rate. We show how persistent differences in growth rates across countries could stem from differential public finance constraints, and differentiate between the case where the public expenditure finances the flow of recurring spending (such as law enforcement), versus the stock of tangible public infrastructure. Although the flow of public expenditure raises productivity, the government should not borrow to finance it as the resulting increase in public debt would lower welfare and the growth rate. With outstanding public debt, the optimal fiscal policy should keep the debt-to-GDP ratio constant in the economy with or without a binding constraint on tax revenues as a share of GDP - current non-durable public goods should be financed only from current revenue. With investment in the stock of public infrastru