I doubt that the police would be interested. Ultimately it comes down to whether other owners in the building regard their use and amenity of the common property to be diminished by this person parking in one of the visitor spaces. If it is rarely causing a problem for other people’s visitors, maybe the committee has judged it to not be worth pursuing or they have it low on a priority list of matters they are attending to.
If you don’t get a response, you could raise use of the visitor parking spaces as a matter for discussion at the next AGM. If others share your concern, you could offer to investigate solutions.