The Sheriff of Nottingham Hypothesis: A Tribute to Theodore Eisenberg

We consider what we call the Sheriff of Nottingham hypothesis: that the government of Brazil, which at the same time is party to litigated cases and the enforcer of tax laws, constantly enacts norms that seek to strengthen its side. We test this hypothesis and observe that litigants adapt to new proportions of decisions favoring tax authorities, with more sophisticated litigants seizing profits beyond those of ordinary citizens. Our proposal is that this dynamic adaptation takes considerable time; therefore, it is possible to detect the effect of changes in the law, despite the selection effect explored by, among others, Theodore Eisenberg.