This is a shock/horror story. Since red kites were re-introduced into the UK, their numbers have increased enormously, in large part due to artificial feeding - at least initially. While true that they are legally protected, they are becoming a problem for conservation managers in some parts of the country because they not only scavenge, but also predate quite efficiently. Blanket legal protection is usually introduced with good intentions, but tends to be difficult to change. Unanticipated consequences for other species often follow so it is scarcely surprising that some take the law into their own hands.
The report quoted a spokesman who suggested that the kite had been shot multiple times with a shotgun, but that it was alive, caught up in a tree with a damaged wing. There was, therefore, a welfare issue because the victim was still alive. However, while the bird may have been hit with several pellets, it seems implausible that evidence could be adduced to suggest multiple shots. A single shotgun cartridge typically contains between 100 and 200 pellets.