With the slightest twitch of her wrist, Emily summoned her wand from its holster. The smooth mahogany felt at home in her grasp. Her eyes searched the cupboard, for any visible signs of tampering, protective charms, anything.. but to no avail.
Emily considered how she might advance. Unlocking it wouldn't be a problem, but if this cupboard was anything like her desk, she wanted to open it and survive...

Looking up briefly at ... whatshisfaceagain? ... she nodded. She wasn't one for stating the obvious, but yes. It was possible that something valuable to their investigation lay inside. "Pensieves perhaps... confiscated items, sensitive documents..." did she need to go on?

"Revelio."
She had to be certain it wouldn't blow them all up first... but it was only security.. they weren't nearly as paranoid as her. Clearly.