Who wants an independent court? Political competition and supreme court autonomy in the argentine provinces (1984-2008)

Political competition should protect judicial autonomy. A host of studies produce evidence that is consistent with this expectation. The influence of political competition operates through two distinct mechanisms: fragmentation and turnover. Most empirical studies treat them as mutually reinforcing. We explain why each of these effects should be most clear when the other one is inactive: when power is concentrated only the expectation of turnover may protect judicial autonomy; when turnover seems unlikely only fragmentation should prevent interferences on the judiciary. We test these hypotheses using an original data set comprising all justices that served in the 24 provincial supreme courts in Argentina between 1984 and 2008. Results of a survival model with competing risks support our argument. The effect of fragmentation is discernible when turnover seems unlikely. The expectation of turnover restrains incumbents particularly when power is concentrated.