(4) A relevant decision may not be taken except
on imperative grounds of public security in respect of an EEA national who: (a) has resided in the UK for a continuous period of at least 10 years before the relevant decision; or... (5) Where a relevant decision is taken
on grounds of public policy or public security it shall, in addition to complying with the preceding paragraphs of this regulation, be taken in accordance with the following principles --(a) the decision must comply with the principle of proportionality; (b) the decision must be based
exclusively on the personal conduct of the person concerned; (c) the personal conduct of the person concerned must represent a genuine, present and sufficiently serious threat affecting one of the fundamental interests of society; (d) matters isolated from the particulars of the
case or which relate to considerations of general prevention do not justify the decision; and (e) a person's previous
criminal convictions do not in themselves justify the decision.