Why Is Aoun Fighting For Karam’s Release?

A Hariri ally offers a theory:

Aoun is worried about certain information Karam might have confessed, which implicates important people in the FPM

This is a tricky issue for Hezbollah. The party can interfere in the process and join Aoun’s campaign to discredit the investigation, but it has so far refrained from doing so to the consternation of its orange ally.

The reason is simple. Hezbollah wants to reach to the bottom of this even if it means “cleaning up” the FPM. If the case against Karam is proven, he (and his collaborators?) would have presented a major security risk to the party and its leader. That is more important than any political alliance that could get strained as a result.