The Knights Holy Cross are a secret order with much power, whilst they without a doubt have controll over what the police or law authority 'sees' when it comes to the righteous act of 'murder' they cannot hinder third party organizations as easily, however, the knights are as stated, a conspiracy theory, a rumor without much to back it up. Whilst the Red Cross corps act as the face of the ancient order.

The Knights Holy Cross would take it upon themselves to rid the world of any alien species, just saying, as it's obvious that the Knights holy Cross only favors the human species. However if everything goes according to the plans of the a knights Holy Cross everyone would die eventually.