Very likely you're looking at the switch in it's "relaxed" position, with the spring pushing the lever to the switch closed position.
I know that on my AD truck, the spring in the lever is compressed with the brake pedal released and when the pedal is pushed, it allows the lever to be pushed by the spring to the closed switch position, and completing the circuit to the brake lights.
I don't know of any way that opening a contact would complete a circuit, unless a normally activated relay were involved.
