March 28 (Reuters) - New documents that could provide clues to the motive of the man who shot dead children and staff at a school in Connecticut last December were set to be released on Thursday by a court.
A 90-day sealing order expires on search warrants that were served on the home and property of Adam Lanza, who killed 26 people at the Sandy Hook Elementary School in Newtown, Connecticut, the second-deadliest school shooting in U.S. history.
Among the items expected to be released by a Connecticut court is a 7 x 4 foot (2 x 1 meter) spreadsheet of past high profile mass murders, designed like a game score sheet with room for Lanza's name at the top.
Discovery of the spreadsheet, which required a special printer, was mentioned in a talk given by police at a law enforcement conference this month. It was first reported by the New York Daily News and has since been confirmed by Connecticut Governor Dannel Malloy.
Family members of the victims were outraged that they had not been notified first about that piece of evidence and demanded more information from authorities investigating the case.
Twenty Sandy Hook first graders and six staff members were shot dead in the attack on Dec. 14 by Lanza. Lanza, 20, killed his mother in their home in Newtown before going to the school, where he also killed himself.
The assault prompted President Barack Obama to call it the worst day of his presidency and reignited a debate on gun violence in the United States. In response to the attack, the National Rifle Association called for armed guards to patrol every public school in the country.
The documents are being released on the same day that a group of Newtown residents plan a protest at the National Shooting Sports Foundation, less than 3 miles (5 km) from the school over the National Rifle Association's opposition to new gun control laws. Newtown residents were enraged after receiving a slew of robo-calls on behalf of the NRA bashing anti-gun laws. (Reporting by Barbara Goldberg; editing by Paul Thomasch and Grant McCool)