THIS REPORT EXAMINED WHETHER PAROLE BOARDS, OPERATING UNDER EXPLICIT DECISION GUIDELINES, ACHIEVED A SUBSTANTIAL SENTENCE EQUALIZATION FUNCTION. DATA ON SENTENCE LENGTH AND TIME SERVED (PRESUMPTIVE RELEASE DATE) WERE OBTAINED FOR 4,471 ADULT CASES APPEARING BEFORE THE FEDERAL PAROLE COMMISSION FOR THE INITIAL SETTING OF RELEASE DATES BETWEEN OCTOBER 1977 AND MAY 1978. ONLY THE MOST FREQUENTLY OCCURRING OFFENSES (INVOLVED IN AT LEAST 50 CASES DURING THE PERIOD STUDIED) WERE ANALYZED. THE CONCEPT OF 'EQUAL TREATMENT' WAS DEFINED AS EQUAL MAXIMUM SENTENCE LENGTHS FOR THE JUDICIAL DECISION AND AS EQUAL TIME SERVED (AS MEASURED BY PRESUMPTIVE RELEASE DATES) FOR THE PAROLE COMMISSION DECISION. 'EQUALLY SITUATED DEFENDERS' WAS DEFINED AS PERSONS WITH SIMILAR OFFENSE SEVERITY RATINGS DEFINED BY THE CONSENSUAL RANKINGS OF THE PAROLE COMMISSION AND SIMILAR PRIOR RECORDS AS MEASURED BY SALIENT FACTOR SCORE CATEGORIES (A MEASURE OF THE FREQUENCY AND SERIOUSNESS OF PAST CRIMINAL CONDUCT). THE MOST STRIKING RESULT WAS THAT FOR EVERY CATEGORY OF EQUALLY SITUATED OFFENDERS, THE COEFFICIENT OF VARIATION WAS MARKEDLY SMALLER FOR THE DECISIONS AS TO TIME SERVED THAN FOR THE DECISIONS REGARDING SENTENCE LENGTH. PAROLE COMMISSION DECISIONS, THEREFORE, WERE LESS DISPARATE THAN JUDICIAL DECISIONS, REGARDLESS OF THE PRIOR RECORD OR OFFENSE SEVERITY OF THE CATEGORY EXAMINED. FURTHER RESEARCH IS NEEDED, HOWEVER, TO CONFIRM WHETHER GUIDELINES NOW IN USE BY THE PAROLE COMMISSION ARE RESPONSIBLE FOR THE DISPARITY REDUCTION REVEALED IN THE DATA. THE FINDINGS ALSO SUGGEST THAT SYSTEMS WITH CONCRETE GUIDELINES FOR REDUCING INEQUITIES MAY HAVE ADVANTAGES OVER OTHER PROPOSED SYSTEMS THAT PLACE THE AUTHORITY FOR SENTENCE REVIEW WITH THE JUDICIARY. FOOTNOTES, TWO STATISTICAL TABLES, AND REFERENCES ARE INCLUDED. (AUTHOR ABSTRACT MODIFIED--AOP)