FORT LAUDERDALE, Fla. — A former Florida sheriff’s deputy is claiming he had no legal duty to confront the gunman who murdered 17 people and wounded 17 others at Parkland’s Marjory Stoneman Douglas High School nearly six years ago, his attorney argued Monday.The legal team representing Broward County Deputy Scot Peterson asked a judge to dismiss the lawsuit brought by the victims’ families and survivors, even though the decision would likely be derided by the public.Attorney Michael Piper told …