Discerning centurions?

It seems when I discern an Imperial I can see whether not not they recently placed centurions. Not sure if this should work because its discern spell unless centurions are a spell? <764hp/764hp || 819m/811m || 734mv/734mv ||325> discern maz You carefully study Mazlare and discern the auras surrounding him. Mazlare is affected by centurions. Mazlare is affected by detect invis. Mazlare is affected by invis. Mazlare is affected by protection from good.