This is not quite as easy as it is being made out to be; these operations will have to be carried out in accordance with HEC Class D - all mean of lifting (hook, attachment, line and PCDS) will have to be certificated in accordance with Part 27/29.
This is no different from the US (which also needs approval in accordance with Part 133); just because 'public use' in the US manages to avoid regulation does not mean that it is OK. The FAA do not condone such practices (read the recent thread on the S92 hoist). Read also the NTSB (and HAI) views on 'public use' aircraft (for the NTSB, the S61 fire fighting accident has a good spread of views).
If this is to be done by HEMS or Police it will have to be done in a considered way; the mere thought of attaching a lifting device to 'harness' hard points sends shivers up my spine. Short Haul is not an ad hoc activity, it has to be done under controlled conditions.
Jim