2003 the Stock Exchange of Thailand measured the implementation of the 15 principles of good governance in the Thai code by each of the 320 listed firms, based on the mandatory
2002 compliance statements. We find that a one standard deviation increase in the code adoption index is related to a 10% increase in average firm value (Tobin’s Q) in the three- year period after introduction of the code, while controlling for firm-specific factors and industry effects. The relation is highly significant and not present prior to the introduction of the code in 2001, suggesting a causal link from code adoption to firm value. Our results confirm the findings of the cross-country studies of Klapper and Love (2004) and Durnev and Kim (2005), namely that in countries with a weak legal system the relation between firm value and corporate governance is positive and strong. La Porta et al. (1998) rate the efficiency of the judicial system in Thailand as 3.25 on scale from 0 to 10, far below the ratings typical for developed countries. Our results show that conclusions of empirical studies on voluntary code adoption and firm value in developed markets – typically finding no significant relation – cannot simply be extrapolated to an emerging market context.