It's an autopsy room, something bad needs to happen. It's practically a horror law. RE2 handles the scenario very well and creates one of the game's best jump scares.
You're down there looking for the key card to open the armory. After one of the morgue drawers opens with an ominous creek, you know something's going to go wrong in a big way. After you pick up the card you were looking for, you find out exactly how wrong it goes.