The USB stick with a sticker

One of the missing USB sticks had a sticker everyone knew. Whoever saw it after the break-in says the sticker was still on it. The clues no longer hand you everything on a plate.

Suspects

• Adolfo, the press adviser: He prepares the statements. This one already mentioned 'ground zero' before anyone knew what had happened.
• Bertina, the substitute MP: She only goes to Parliament when someone is absent. That day nobody was absent.
• Constantino, the party's IT man: He formats USB sticks and keeps the ones with stickers.
• Delfina, the weekly paper's journalist: She has a friend in every office and a source in every kitchenette.