I'm doing well with my Early, Expert, GA French campaign (vanilla VI, 2.01). It's just shy of 1250 and I'm winning on points, and allied with the Pope -- usually as a Catholic faction I take it as a point of pride to ally with the holy father, unless I'm the HRE of course.

Although we're not whaling on each other with armies, and have been allied for much of the game, His Popeness has apparently decided to make my life miserable by sending a 6-star Inquisitor through my wealthiest territories and burning generals and governors there. My greatest frustration was when my 8-acumen governor of Flanders (who was no slouch on the Piety, either) was burned at the stake.

There's no stopping this 6-star nightmare (assassins are useless), but that's not really the point of this thread. I was wondering, is there any logic behind the AI's decision of who to go after with their inquisitors? Why does the Pope keep coming after me? Why not go after the uppity Spanish, who are about as big as I am? How do these targets get chosen?