Kingston Police Chief Egidio Tinti, on the job less than a month, is trying to meet the public’s demand for more and more aggressive policing, even as the department’s manpower and overtime levels fall to their lowest level in more than a decade. The department, which five years ago had 81 sworn police officers on the roster, is currently down to 71 and retirements are expected to drop that number to 69 by the end of the year.