The use for sentence enhancement purposes of prior convictions invalid on grounds directly related to factual accuracy should be prohibited because such use would violate due process and contravene the policies underlying criminal sentencing. With regard to prior convictions unconstitutional on grounds not directly related to the ascertainment of factual guilt, the argument for permitting enhancement use is strong. Such convictions are, after all, reliable indicators of past criminality. However, the use of such convictions would compromise judicial integrity. It is extremely difficult to discern whether a given constitutional defect does or does not bear on the ascertainment of factual guilt. Consequently, prior convictions tainted by constitutional defects which do not undermine factual accuracy should not be used for sentence enhancement. 275 notes