The Article also provides for extradition of drug offenders, although a Party has a right to refuse to extradite a suspect if "competent authorities consider that the offense is not sufficiently serious." A 1971 amendment to the Article grants nations the discretion to substitute "treatment, education, after-care, rehabilitation and social reintegration" for criminal penalties if the offender is a drug abuser. A loophole in the Single Convention is that it requires Parties to place anti-drug laws on the books, but does not clearly mandate their enforcement, except in the case of drug cultivation.