Newtown Police Report May Not Be Done Until Sept. A Connecticut state police spokesman says "it could be as long as September" before a report on the investigation into the Newtown school shooting is finished. Spokesman Lt. J. Paul Vance said Wednesday that authorities are working to complete the investigation as quickly as they can but want to make sure they do a thorough and accurate job. Twenty-year-old Adam Lanza fatally shot 20 first-graders and six educators at Sandy Hook Elementary School on Dec. 14 before killing himself as police arrived. Danbury State's Attorney Stephen Sedensky III, who is leading the investigation, estimated in January that the investigation would be completed in the summer, perhaps in June.