Constitutional court judges maintain to be independent, apolitical actors, even though they get nominated by political elites. So far, much of the research has focused on the legal output of courts in order to show that judges are political animals. Studying outcomes often plagued by endogeneity issues (e.g., when using votes to predict votes), or is simply not possible in some contexts due to non-disclosure of individual voting records. Alternatively scholars employ a party-label heuristic and infer from the ideological position of the nominating party to the ideological position of the judge. But do those ideological differences between judges become behaviorally relevant? In this paper, we show that two pieces of evidence that judges nominated by different parties seem to behave differently. First, we study at the composition of three-judge panels (chambers) of the German Federal Constitutional Court using Chamber decisions from 1998-2011 and show that homogenous panels have been actively avoided. Second, we analyze the court’s replacement rules for absentee judges for the composition of chambers. We show that in situations where mechanically following the rules of procedure to replace absentee judges would lead to homogenous panels, the likelihood to deviate from those rules are systematically higher. Thus, the court actively seek to avoid such homogenous chambers and are more likely to deviate from the rules of procedure in such cases in order to appear politically unbiased.