Purpose – The purpose of this paper is to construct an econometric model of the determinants of private investment with a particular focus on the impact of democracy on investment. Design/methodology/approach – The first step was to econometrically derive the long-run elasticities; then to modify the Fiji computable general equilibrium (CGE) model to incorporate the investment function. Also the econometrically derived long run elasticities in the CGE model were used. Findings – It was found that democracy has a positive and statistically significant impact on private investment in Fiji. The paper's simulation of Fiji becoming a fully democratic country on investment and other macroeconomic fundamentals, based on a CGE model, reveals that real gross domestic product and real national welfare increase by around 0.01 and 0.05 per cent, respectively; government savings and revenue performance improves; there is a trade balance surplus; and both private consumption and disposable income increase by around 0.05 and 0.12 per cent, respectively. Originality/value – This is the first study that uses a CGE model to examine the impact of democracy, via investment, on other macroeconomic fundaments. No other study is known to have modelled democracy in a CGE framework.