The government in the UK came up with a phrase some years ago called "Joined-up government". The idea was that many government services are delivered in a disjointed and sometimes contradictory way, and the only way to improve service delivery was to "join up" the bits that weren't talking to each other.
Here is a classic case of non-joined up government. The truck on the left belongs to Council - local government. The substation on the right belongs to Energy Australia - a state government corporation. I can't verify this, but it is my belief that the man in the truck would never think to report the graffiti on the substation to Energy Australia - it is not part of his "brief". His job is to clean graffiti that has been reported to Council, not to report graffiti to other agencies.
The problem with this is that the truck has just driven past two Council assets - a playground with an attached building. The playground equipment and the building have both been tagged, as has the sign out the front of the playground. Once vandals start tagging something in an area, they seem to branch out and start tagging everything in that area. They might start by tagging in the playground, and when that goes unnoticed and unremoved, they move on to tagging the substation - or vice versa.
Clearly, if you want to dissuade them from tagging in a particular spot, you need to clean up everything in that area. Vandals need to be shown that, for want of a better word, the Public cares about this space and doesn't want to see their crap sprayed all over it. Vandals need to be shown that they don't own this space - we, the taxpaying, respectable members of society own it.
There is no point in Council cleaning their bit, and leaving 50% of the targetable assets in this area in a filthy state, because that just brings the graffiti back.
Joined-up government does not require the establishment of committees or a new bureaucracy - it just requires a change in thinking. The driver of the truck in the above photo needs to develop a mindset of, "My job is to ensure all graffiti is removed from an area, even if I am not the one to do it all. My job is partly to clean and paint over vandalised property, and partly to report graffiti that is on property that is outside my remit".