An amendment to mandate that a portion of federal highway funds be withheld from States that do not enact laws requiring the suspension or revocation of driver's licenses of persons convicted of drug-related criminal offenses. The amendment requires states to impose suspensions of at least six months for a first conviction and at least one year for repeat convictions within a five-year period and also requires that 5 percent of federal highway funds be withheld the first year that a state fails to comply and that 10 percent be withheld for every subsequent year of noncompliance.