Guideline 4, 21. (d) Criminal law should not be an impediment to measures taken by States to reduce the risk of HIV transmission among injecting drug users and to provide HIV-related care and treatment for injecting drug users. Criminal law should be reviewed to consider: the authorization or legalization and promotion of needle and syringe exchange programmes; the repeal of laws criminalizing the possession, distribution and dispensing of needles and syringes.