What is a scattergun approach?

[bartholomew]

"The media are always helpful at publishing photos of criminals wanted by us but often this is done in a scattergun approach and it loses some impact."

[Fern57]

Well, I found this:

The scattergun approach in advertising, is when you don't try to isolate your potential customers from the general population. While you may find a few people who will buy your product, the majority of your advertising dollar is being wasted on people who aren't a potential customer.

here:
http://www.resource-box.com/scattergun-approach--10801.h tml

So I suppose it works in a similar way.

[Clanad]

A scattergun is a euphemism for a shot gun, used in hunting.  The shotgun, when fired releases numerous small pellets rather than a single bullet.  These pellets can and do strike other things than the intended target.  The word picture, then, in your reference is one of the media not "aiming" for a precise target but, rather, sending the photos to useless sources as well... 

[Ouisch]

In the US, we say "scattershot", which is based on the same premise as "scattergun", with little pellets that burst and fly all over, many missing the original target.  Using a scattershot approach to something is similar to "throwing a bunch of (whatever) against the wall and see what sticks."