Some jurisdictions have the concept of "railway police" who are sworn officers protecting the railway land. See the US section for example: https://en.m.wikiped

Some jurisdictions have the concept of "railway police" who are sworn officers protecting the railway land. See the US section for example: https://en.m.wikipedia.org/wiki/Railroad_police https://en.m.wikipedia.org/wiki/Railroad_police They still work for the railway so there is some conflict but I don't know that they'd by any more vigilante than regular police, and they have a special status with the states compared to security guards