17. Decisions taken on the grounds of public policy, public security or public health (the relevant grounds) shall be taken in accordance with the following principles—
(a)the relevant grounds shall not be invoked to secure economic ends;
(b)a decision taken on one or more of the relevant grounds shall be based exclusively on the personal conduct of the individual in respect of whom the decision is taken;
(c)a person’s previous criminal convictions shall not, in themselves, justify a decision on grounds of public policy or public security;
(d)a decision to refuse admission to the United Kingdom or to refuse to grant the first residence permit to a person on the grounds that he has a disease or disability shall be justified only if the disease or disability is of a type specified in Council Directive 64/221 EEC.
(e)a disease or disability contracted after a person has been granted a first residence permit shall not justify a decision to refuse to renew his residence permit or a decision to remove him.
(f)a person shall be informed of the grounds of public policy, public security or public health upon which the decision taken in his case is based unless it would be contrary to the interests of national security to do so.