Obviously you guys aren't getting the clues so I'll lay it out. I'm the investigator and I know lastings is mafia.
When Aqua made his implication yesterday, I at least knew he couldn't be the investigator. While it was still possible he could be the doctor, the likelihood was much greater that he was mafia. I couldn't afford to give him the chance to specifically claim investigator and have people start unvoting him. At that point, I'd either be forced to come forward on Day 1 or possibly let Aqua run the town.