who decides?

The word "eugenics" was coined in 1883 by the English scientist Francis Galton, a cousin of Charles Darwin, to promote the ideal of perfecting the human race by, as he put it, getting rid of its "undesirables" while multiplying its "desirables" -- that is, by encouraging the procreation of the social Darwinian fit and discouraging that of the unfit. In Galton's day, the science of genetics was not yet understood. Nevertheless, Darwin's theory of evolution taught that species did change as a result of natural selection, and it was well known that by artificial selection a farmer could obtain permanent breeds of plants and animals strong in particular characteristics. Galton wondered, "Could not the race of men be similarly improved?"