Comment by sandworm101

There is specific Italian law about return of art. This would normally apply to people who stole the art but a careful lawyer could use this law to negotiate a reduced punishment for organized crime charges. If the art theft is described as a part of a larger criminal enterprise, then the return of that art could trigger a 2/3 reduction in punishment. See below (translated by google).

https://documenti.camera.it/leg18/dossier/testi/gi0031b.htm

"is committed by the person who has collaborated in identifying the co-conspirators or has ensured evidence of the crime or has effectively worked to prevent the criminal activity from being carried to further consequences or has recovered or had recovered the cultural property subject to the crime (penalty reduced from one third to two thirds)."