Chain of Evidence by Ridley Pearson

it—like silencing an alarm clock. She did not look up at him but kept her head aimed down at her desk and the paperwork that seemed to absorb her.
    Dart had a lookout—an accomplice. An angel on his shoulder.
    The listing cart’s front right wheel chirped. Dart awkwardly navigated it to a position in front of Narco. He knocked, waited, and then knocked again. With no reply, he slipped his hand beneath the stack of green rags and removed the speed key. The fact that he was violating regulations distrubed him. If caught, he would have some tough explaining to do. He was the cop turned criminal, and for a moment he couldn’t bring himself to do this. But the hope that Kowalski, not Zeller, was responsible for the murder/suicide of Lawrence, and the possibility of connecting Lawrence to Stapleton drove him on—anything to quiet his guilt.
    With the speed key the door opened effortlessly. It was illegal in all fifty states to own such a device, and Dart suddenly understood why.
    As in hotels, the housecleaners at Jennings Road blocked open office doors as they worked. Dart did just that, though only partially screening the room inside so that the closet used as a vault to contain files remained obscured from the hallway.
    He switched on the interior light, emptied a trash can into the hopper on his cart, and placed a beat-up feather duster on the desk top closest. His watch face read 1:03. The cleaners would be arriving any minute and would start on the first floor. He had plenty of time.
    The file room closet was locked, but the speed key made quick work of it. The light switch was mounted on the wall outside. Dart studied his situation, planning, predicting every movement required should his pager alert him to a visitor. He had to keep all actions to a minimum, and so rather than venture inside the room, he stood there figuring how to avoid being caught. He relocked the file room door, so that once shut it would be locked and not require him to fiddle with it. He used a green rag to block it open, and tested that by kicking the rag free, the door would close on its own. Then, with the light on, he stepped inside and looked to judge the line of sight: If someone showed up unexpectedly, this person would quickly have a clear sight of the open file room.
    The light switch on the wall was on the far side of the hinges, meaning that Dart would have to kick the rag out of the way, get himself around the door, helping it close as he went, and then hit the light switch. But this light going off would be picked up even sooner by someone entering because the office door to Narcotics had an institutional smoked-glass panel, and a change in background light would be noticeable. He reviewed the situation; deciding he had things in the right order, rehearsed them once while counting in his head. Four to five seconds , he guessed. When combined with the five or so seconds that Abby needed to alert him, it would be too long.
    He grabbed the mop and headed directly to the hallway’s broom closet, filled the rolling bucket from the soapstone sink, wetted the mop and, carrying a yellow plastic sandwich board warning of a WET FLOOR , hurried to the end of the hall near the stairs and the elevator. He mopped the floor furiously, making it as wet as possible, then placed the sandwich board in the center of the hall. With all this water he hopefully had bought himself some extra time while also slowing down any approach.
    Back inside Narco, Dart unlocked the file room for the second time, blocked the door open with the rag, and switched on the light.
    The room was crowded with gray metal utility shelving along all walls and a pair of opposing stacks in the center. All the shelves were crammed with folders.
    Dart checked his watch. This could take a while.
    A rolling stepstool allowed him access to the top shelves, which was where he found the L’s. Dart was surprised by the number of files, each representing a Narco investigation, an arrest, or