Because of the secrecy of the review process, analysis of case selection criteria with statistical tools had to be based on the facts of grants and denials until 1965, when the papers of Justice Harold H. Burton became available. Complete docket books recording the case selection votes of each justice for the 13 terms that Burton sat on the Court (1945-1957) were found in the papers. The Burton data made it possible to analyze case selection and its relationship to the work of the Supreme Court and to evaluate the validity of previous hypotheses of how case selection proceeded. For example, one theory explored the possibility that in Federal Employer's Liability Act (FELA) cases, a subgroup of justices manipulated others on the Court to gain the outcomes it preferred on the merits. This was possible because only four affirmative votes were needed to review, while five were necessary to win. However, the Burton papers showed that in many instances one to six votes were cast for review, too many to suggest the operation of a 'certiorari block.' Another hypothesis assumed that the justices' primary concern was to reduce their workload, which they accomplished by using a set of agreed upon cues to choose cases for review. This analysis suggests that Supreme Court justices during the Burton period shared a powerful conception of the role of their institution, which appears to have sharply limited the level of disagreement that could otherwise have been anticipated in case selection voting. Consensus on the norms of judicial behavior also appears to have discouraged these justices from either combining forces to achieve the results they preferred on the merits of the cases or from voting individually in a way that would indicate routine calculation of probable outcomes in the case selection process. Tables and 31 footnotes are provided.