We examine whether the differences in the legal origins of countries (Common Law versus Civil Law) can explain the variations in the price efficiencies of the stock markets of different countries. Based on multifractal detrended fluctuation analysis of the daily stock indices of 34 countries over 21 years, we find that the stock price indices in Common Law origin countries show greater price efficiency than the stock price indices in Civil Law countries. These results provide additional evidence that the legal origins of countries affect their economic activities and outcomes.