Throughout the history of humanni religious tradition are the
Faith Healers. Most of these bring short term relief to pain and suffering by psychosomatic means. It can look like magic, but it isn't. Unless it is.
Picture Imperial agents who track down Faith Healers looking to see who is only a phony, who is a possibly dangerous real healer. Sure, some real psis who think they are touched by God's grace (or what ever the locals call it) can be left alone, sometimes. But most hidden psis, whether or not they know they are psis, need to be dealt with.