The trailer that moved house

A trailer seized in a drugs raid should have been locked in a criminal police warehouse. It turned up in a builder's warehouse instead, and nobody can say who towed it. Four people and one piece of evidence: one person per row, one per column. Whoever is left alone in the evidence's room is the one you're looking for.

Suspects

• Abel, the storekeeper: He has a list of everything that was seized. The trailer just isn't on it.
• Beatriz, the site manager: She insists nothing gets onto the site without paperwork. The trailer, she says, came in on its own.
• Custódio, the tow truck driver: He's been towing for twenty years and has never asked what's hitched behind him.
• Dália, the inventory inspector: She counts the seized goods twice a year. This year she's on her third count.