IN THE LATE 19TH CENTURY AMERICA'S STATE SUPREME COURTS WERE MAINLY REACTIVE BODIES. POPULATIONS AND CASELOADS WERE SMALL, THE JUDICIAL SYSTEM WAS DEMOCRATIC IN THEORY, AND THE STATE'S HIGHEST COURTS WERE OPEN TO EVERYONE REGARDLESS OF WEALTH OR POLITICAL INFLUENCE. AS STATE POPULATIONS GREW, ACCESSIBILITY PRODUCED LARGE CASELOADS. SUPREME COURTS IN THE LARGER STATES SOMETIMES ISSUED 400 TO 500 OPINIONS A YEAR. MANY OF THESE OPINIONS WERE SHORT AND PERFUNCTORY AND THE COURTS WERE CRITICIZED FOR THEIR BACKLOGS AND THE MECHANICAL QUALITY OF THEIR DECISIONS. THIS SPURRED MOVEMENTS FOR JUDICIAL REFORM. DURING THE 1900'S THIS REFORM HAS PROCEEDED PAINFULLY. BY 1970 MOST OF THE LARGE AND MEDIUM-SIZED STATES HAD CREATED INTERMEDIATE APPELLATE COURTS AND HAD GIVEN THE SUPREME COURT DISCRETION OVER THE CASES IT WISHED TO HEAR. THE SUPREME COURTS RELINQUISHED THEIR ROLE AS PRIMARY CORRECTOR OF JUDICIAL ERRORS AND, INSTEAD, BEGAN TO CONCENTRATE ON APPEALS THEY THOUGHT WERE MERITORIOUS OR THAT RAISED IMPORTANT ISSUES OF POLICY OR PRINCIPLE. BETWEEN 1940 AND 1970 THE COURTS WITH THE HIGHEST DEGREE OF DISCRETION WROTE THE FEWEST OPINIONS. THESE OPINIONS TENDED TO BE LONGER AND CITED MORE CASES. THEY ALSO REVERSED LOWER COURT ORDERS MORE OFTEN AND CONTAINED MORE DISSENTS AND CONCURRENCE. THERE WERE FEWER COMMERCIAL AND REAL-ESTATE CASES (THE TRADITIONAL STAPLES OF STATE SUPREME COURT BUSINESS) AND MORE CRIMINAL AND PUBLIC LAW CASES. THE SCREENING PROCESS IS NOW A PROBLEM. THE DEBATE SURROUNDING VARIOUS SCREENING METHODS IS REVIEWED. TABLES AND GRAPHS PRESENT STUDY DATA. AN APPENDIX GIVES STUDY METHOD. REFERENCES ARE FOOTNOTED. (GLR)