The Law of Unintended Secondary Effects provides for the imposition of the death penalty. In this case, it is insecticide rather than homicide. In gardening and agriculture, “natural” pest control includes the introduction of beneficial insects to prey on insect pests. Unfortunately, some of these beneficial insects become pests themselves. The asiatic ladybug is still available by mail-order, even though they have become a nuisance in the US because of their habit of nesting indoors. A vacuum cleaner is recommended for removing them; they leave a nasty stain if you squash them.
In the UK, the problem is more serious. There are similar native species that are being destroyed by being out-competed by the aliens, or even by the more direct method of being eaten by them. The various native species may go extinct as early as 2008.