Game concept
Imperial Policy Faction
The game also links it as Imperial Policy, Imperial Policy Factions.
From the game's encyclopedia
The Imperial Policy Faction seeks to change the Imperial Policy of the Realm, adopting a new Law selected by the faction leader.
The game's text for patch 1.20.1.2. Words in blue are entries of the encyclopedia: hover one to read it, as in the game.
Imperial Policy Faction is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "The Imperial Policy Faction seeks to change the Imperial Policy of the Realm, adopting a new Law selected by the faction leader." It is part of Faction. The game also links it as Imperial Policy and Imperial Policy Factions. Patch 1.20.1.2, from game/common/game_concepts/00_game_concepts.txt and game/localization/english/game_concepts_l_english.yml.
Source: game/common/game_concepts/00_game_concepts.txt, game/localization/english/game_concepts_l_english.yml and the English localisation, Crusader Kings III 1.20.1.2.