He is not the only person to have have illegal weapons. Raid the local politicians or any ordinary street fighter or gangster in UP or Bihar, they all have country made guns and illegal weapons, so whats the difference. Sanjay got it from the Underworld suppliers and the others get it from unknown sources. Sanjay had no direct involvement in the 93 Blast. If ordinary pick pocketers use a switch knief, then a person like Dutt has Ak-56.