In what sort of timescale is this crime ?
The British Foreign Office advises that crime levels are low on SM and the US State Department has the lowest level of " take the usual precautions " advice. Whilst these isolated incident are regrettable they are still extremely isolated when compared with the huge number of visitors.
I've travelled to a lot of the Caribbean over the years and SM seems far more affluent and safe than most.
Take a look at mainland France if you want an idea of what serious crime figures are about.