A/HRC/23/48 (e) Measures to discourage demand should conform with general principles associated with the rule of law, i.e., should not make it an offence to commit an act (including purchasing a particular service or produce) in circumstances in which the purchaser could not reasonably be expected to be aware that he or she was committing an offence, for example if a particular product or service is made or provided by someone who has been trafficked, unless there is evidence that the purchaser was negligent. This means that States should publicize any changes in the law that make it an offence to purchase certain types of services or products made or provided by people who have been trafficked, and provide unambiguous information to potential purchasers about such services or products; (f) Measures to discourage demand which involve restricting the exercise of the human rights, including by individuals who are judged to be especially vulnerable to being trafficked, should conform with the principle of proportionality (i.e., they must be appropriate to achieve their protective function; they must be the least intrusive instrument amongst those which might achieve the desired result; and they must be proportionate to the interest to be protected); (g) It is necessary to ensure that anti-trafficking measures do not adversely affect the human rights and dignity of persons, in particular the rights of those who have been trafficked, migrants, internally displaced persons, refugees and asylum seekers. States should actively monitor the impact and possible side effects of measures to discourage demand and take appropriate action to address any unintended side effects which restrict the exercise of human rights; (h) States should seek the views of representatives of any particular group of people who would potentially be affected by measures to prevent human trafficking in a significant way and take these views into account when designing measures to discourage demand. Seeking the views of such people means collecting relevant information from people who, on account of their experience, are likely to be wellinformed about the shortcomings, gaps or unintended consequences of existing policies and practices. In particular, as highlighted by the Committee on the Rights of the Child, States have a responsibility to listen to and take into account the views of children who may be impacted by any measures to discourage demand. 21