THE HARMLESS ERROR DOCTRINE ENABLES AN APPELLATE COURT TO AFFIRM A CRIMINAL CONVICTION DESPITE ERRORS COMMITTED BY THE TRIAL COURT, PROVIDED THE DEFENDANT WAS NOT PREJUDICED. IMPLICIT IN THE DOCTRINE IS RECOGNITION THAT THE DEFENDANT IS ENTITLED TO A FAIR TRIAL BUT NOT A PERFECT TRIAL. WHEN ERROR IS NOT OF CONSTITUTIONAL MAGNITUDE, IT IS USUALLY DEEMED HARMLESS IF IT DOES NOT AFFECT SUBSTANTIAL RIGHTS OF INVOLVED PARTIES. THE FEDERAL TEST FOR HARMLESS NONCONSTITUTIONAL ERROR IS SOMEWHAT LESS DEMANDING THAN THE STANDARDS FOR REVIEWING NONCONSTITUTIONAL ERROR. ALTHOUGH IT IS CLEAR THAT CONSTITUTIONAL ERROR IS NONPREJUDICIAL ONLY IF HARMLESSNESS IS PROVED BEYOND REASONABLE DOUBT, METHODS FOR DETERMINING WHETHER THIS STANDARD OF PROOF IS MET REMAIN UNCERTAIN. AN UNSATISFACTORY ELEMENT OF THE OVERWHELMING EVIDENCE TEST IS ITS FAILURE TO DETER PROSECUTORIAL MISCONDUCT. IN ADDITION, THE HARMFUL EFFECT OF READING A 'COLD RECORD' IS MAGNIFIED WHEN A COURT APPLIES THE OVERWHELMING EVIDENCE TEST. WITH THE CUMULATIVE EVIDENCE TEST, HARMLESSNESS IS ESTABLISHED WHEN ERRONEOUSLY ADMITTED EVIDENCE IS MERELY DUPLICATIVE OR CUMULATIVE OR UNTAINTED EVIDENCE, SINCE ERROR ADDS NOTHING MATERIAL TO A CASE. THIS TEST HAS BEEN REJECTED BY THE U.S. SUPREME COURT AND IS SUBJECT TO MANY OF THE SAME CRITICISMS AS THE OVERWHELMING EVIDENCE TEST. A FURTHER TEST FOR MEASURING HAMRLESSNESS REQUIRES A COURT TO ASSESS THE PARTICULAR CONSTITUTIONAL VIOLATION IN ISOLATION. UNDER THIS TEST, AN APPELLATE COURT DISREGARDS UNTAINTED EVIDENCE AND INQUIRIES AS TO WHETHER ERROR IS PREJUDICIAL. THE PREFERABLE STANDARD FOR ASSESSING HARMLESSNESS IS THE REASONABLE POSSIBILITY THAT ERROR CONTRIBUTED TO A CONVICTION. THE PRIMARY ADVANTAGE OF THIS TEST IS THAT IT PERMITS A COURT TO ANALYZE THE IMPACT OF TAINTED EVIDENCE WITHIN THE CONTEXT OF OTHER EVIDENCE IN THE RECORD. THE AIM OF ANY TEST FOR HARMLESSNESS MUST BE TO PREVENT A CONVICTION BASED IN ANY WAY ON ERROR. CASE LAW IS CITED.