By Russell McCulley ST. FRANCISVILLE, Louisiana, Sept 7 (Reuters) - A jury began deliberating on Friday the fate of a couple accused of negligent homicide in the flooding deaths of 35 elderly people at their Louisiana nursing home during Hurricane Katrina. Salvador and Mabel Mangano, ages 67 and 65, respectively, face 35 counts of negligent homicide and 24 counts of cruelty to the infirm, with a combined maximum sentence of 415 years each if convicted of all charges. Katrina's 20-foot (6-meter) storm surge trapped and drowned residents at the Manganos' St. Rita's nursing home near New Orleans in one of the worst tragedies of the Aug. 29, 2005, storm that killed more than 1,400 people along the U.S. Gulf Coast. Prosecutors accused them of negligence and greed for failing to evacuate their residents, saying they did not heed government warnings and did not want to spend money to transport their residents elsewhere. "Thirty-five frail, elderly, sick souls died on August the 29th, 2005. Twenty-four others -- mothers, fathers, brothers, sisters -- all sick and elderly, needing 24 hour-a-day care, suffered needlessly," prosecutor Paul Knight said in closing arguments. "And it happened for one simple, inescapable reason. Because they were there. Because they were there. They didn't have a choice to be somewhere else," Knight said. But defense attorneys said the Manganos, who stayed at the nursing home during the storm, did not think floodwaters would reach the building and believed their residents were too frail to move. They blamed local and federal governments for building poorly constructed levees that allowed the floodwaters in and for failing to adequately warn of the storm's dangers. No mandatory evacuation order was given, they said. "Sal and Mabel believed they were in a safe place. If they believed it would flood, would they have stayed there (at St. Rita's) themselves?" attorney John Reed told the jury. The government failed "woefully and horribly" in "its duties to keep us safe and its duty to warn us of the danger that was there," he said. The Manganos' nursing home is in St. Bernard Parish, a low-lying area southeast of New Orleans that was devastated when Katrina's storm surge overwhelmed protective levees. They managed to save 24 of their residents, but face cruelty to the infirm charges for each of them. Their trial, which began with opening arguments on Aug. 16 and included testimony by Louisiana Gov. Kathleen Blanco, was moved 125 miles (201 km) northwest to St. Francisville to get an unbiased jury.