CAT/C/70/2 members of society and will continue to do so for a considerable time to come. The Subcommittee and national preventive mechanisms must be conscious of the “do no harm” principle as they undertake their work. This may mean that national preventive mechanisms should adapt their working methods to meet the situation caused by the pandemic in order to safeguard the public; staff and personnel working in detention facilities, including healthcare staff; detainees; and themselves. The overriding criterion must be that of effectiveness in securing the prevention of ill-treatment of those subject to detaining measures. The parameters of prevention have been widened by the extraordinary measures that States have had to take. It is the responsibility of the Subcommittee and of national preventive mechanisms to respond in imaginative and creative ways to the novel challenges they face in the exercise of their mandates related to the Optional Protocol. 15