participate in the control or management of, the association, or to organize or train any member or adherent of the association. The Minister is empowered to prohibit any uniform or dress to be worn in public by members or adherents of a political or quasi-military association involved in the activities mentioned in the previous paragraph, or any uniform or dress indicating an association with a political organization or with the promotion of a political object. Wearing such a uniform or dress in contravention of the Minister's order is an offence. In addition, if the Minister considers it to be in the national interest to do, he may prohibit the "manufacture, sale, use, wearing, display or possession of any flag, banner, badge, emblem, device, uniform or distinctive dress or any part thereof". Currently, the only emblem or device that is prohibited is one "in the form of a 5-pointed red star or a hammer and sickle in circumstances which raise a reasonable presumption that the emblem or device was intended or was likely to be used in a manner prejudicial to the interests of Singapore or to promote or foster a purpose prejudicial to or incompatible with peace, welfare or good order in Singapore". It is a crime for a person to be present at or to attend any meeting or assembly organized for the participants to train or drill themselves or to be trained or drilled "in the use of arms ... or for the purpose of practising military exercises, movements or evolutions". It is also a crime to train or drill other people in these manners or to take part in the control or management of an association whose members are so trained. The prohibition does not apply to members of the Singapore Armed Forces, the police, a legally constituted volunteer or local force, a visiting force lawfully present in the country, or any organization or association exempted by the Minister. Preventive detention Chapter II of Part II of the ISA, which allows for preventive detention (also known as detention without trial), is the most conspicuous feature of the Act. It confers on the executive a discretionary power to arrest and detain without trial, when necessary, a person with a view to prevent "that person from acting in any manner prejudicial to the security of Singapore or any part thereof or to the maintenance of public order or essential