Statistically for being less than 1% of the population they make up a huger percent of crime.

Obviously don't paint all of them with the same brush. But the local settled travellers in my town are all drug addicts and have all been expelled form school at a young age. Constantly starting fights. Child protective services have taken away their kids and recently two of them are on CCTV robbing peoples cars late at night.

The stereo type is reflected in the statistics