Before he had taken the package to Sullivan's mailbox, Billy had unlocked the service room inside the Mall's Male Public Conveniences. Billy was posing as the cleaner, to whom he had given a bribe for the key as well as to go some where else for the morning. The service room was the perfect place for Billy to hide. On getting The Rat Faced Faggot's phone call, Billy went to the exit and placed the "Out Of Service" notice board outside. Then Billy proceeded to watch the rear of the Mall for Sullivan's arrival.
In his jacket Billy had two separately padded copies of the CD. One copy was in a pocket, the other was hidden inside the jacket lining. Billy also had two sets of crude photocopies which he had made of the several years of payments made to Sullivan and some others who could be Cops. As with the CD's, one of the two sets was hidden within his jacket lining; this was a precaution against his evidence going astray later.
Finally, after about half an hour, Sullivan arrived and headed for the Public Conveniences. Billy waited until Sullivan was close and then raced to the service room and locked the door. From inside, Billy was able to watch Sullivan pace around impatiently. Carefully Billy unlocked the door. Eventually Sullivan decided to take a leak. This was the moment that Billy had been waiting for.
Creeping out and surprising Sullivan from behind, Billy clubbed him with his gun and then cuffed him. Then Billy dragged Sullivan into the service room. Just to relieve his stress, Billy taunted Sullivan. Sullivan, a liar to the core, continued the pretence of being an honest cop. But when Billy convincingly threatened to kill him, Sullivan's facade broke and he said that he had erased Billy's files. Billy was enraged, not that it made any difference to the plan, it just meant that some amendments would be needed.
Billy now dragged Sullivan outside into the Mall. There were now several people about, hoping to pay a call. Billy called to them to call the cops. Billy had considered calling the cops himself, but only as a last resort as this way he would get more attention, and so would any potential friends of Sullivan. When Sullivan screamed for help, Billy shot him in the arm to shut him up. By the time the cops finally showed up Billy had shot Sullivan in both of his arms and legs. Sullivan would be in hospital for a week or two and it might be months before he could walk again.