Why did Roman emperors regulate private associations called collegia?

Roman emperors viewed collegia—private associations such as trade guilds, burial societies, and religious groups—with suspicion, leading them to impose strict regulations on these organizations.1

To maintain control and ensure social order, the imperial government mandated that no collegium could be founded without explicit state authority. Furthermore, the state closely regulated their specific legal capacities, such as their rights to manumit slaves or accept legacies. By the reign of Emperor Diocletian, the government began to more aggressively exploit these guilds to serve the interests of public authority, eventually attempting to restrict membership to a hereditary caste of artisans to better manage financial and tax-related demands.12