We analyze a large, anonymous labour market in which firms motivate their workers via relational contracts. The market is frictionless and features on-the-job search, in that all acceptable vacancies are immediately filled and the employed compete with the unemployed for vacancies. While firms and workers are ex ante identical, the unique equilibrium exhibits a continuous distribution of contracts in which high wage firms have higher retention rates, more motivated workers and higher productivity. The model thus generates dispersion in wages, productivity and human resource strategies, and gives rise to endogenous job ladders. An exogenous increase in on-the-job search increases the quantity of jobs but decreases their quality; with sufficient on-the-job search there is full employment, and wage dispersion rather than unemployment motivates workers.

We propose a simple model of racial bias in hiring that encompasses three major theories: taste-based discrimination, screening discrimination, and complementary production. We derive a test that can distinguish these theories based on the mean and variance of workers’ productivity under managers of different pairs of races. We apply this test to study discrimination at a major U.S. retailer using data from 48,755 newly hired commission-based salespeople. White, black, and Hispanic managers within the same store are significantly more likely to hire workers of their own race, consistent with all three theories. For black–Hispanic pairs, productivity variance is lower for same-race pairs than cross-race pairs, implying that screening discrimination dominates. For white–Hispanic pairs, mean productivity is higher for same-race pairs, indicating a combination of screening discrimination and complementary production. For white–black pairs, biased hiring implies the presence of discrimination, but productivity results suggest the effects of the three forms of discrimination offset one another.

We explore costly deliberation by two differentially informed and possibly biased jurors: A hawk Lones and a dove Moritz alternately insist on a verdict until one concedes. Debate assumes one of two genres, depending on bias: A juror, say Lones, is intransigent if he wishes to prevail and reach a conviction for any type of Moritz next to concede. In contrast, Lones is ambivalent if he wants the strongest conceding types of Moritz to push for acquittal. Both jurors are ambivalent with small bias or high delay costs. As Lones grows more hawkish, he argues more forcefully for convictions, mitigating wrongful acquittals. If dovish Moritz is intransigent, then he softens (strategic substitutes), leading to more wrongful convictions. Ambivalent debate is new, and yields a novel dynamic benefit of increased polarization. For if Moritz is ambivalent, then he toughens (strategic complements), and so, surprisingly, a more hawkish Lones leads to fewer wrongful acquittals and convictions. So more polarized but balanced debate can improve communication, unlike in static cheap talk. We also show that patient and not too biased jurors vote against their posteriors near the end of the debate, optimally playing devil’s advocate. We shed light on the adversarial legal system, peremptory challenges, and cloture rules.