Because the president can seize stuff from news outlets when he's investigating a crime:
Asked to address the controversial seizure of phone logs from Associated Press journalists by the Department of Justice, President Barack Obama on Thursday said he had no regrets for prosecuting individuals responsible for leaking classified information because they placed the country at risk.
"I make no apologies and I don't think the American people would expect me as commander-in-chief not to be concerned about information that might compromise their missions or might get them killed," he said, standing alongside Turkish Prime Minister Recep Tayyip Erdogan in the White House Rose Garden.
I wonder how far this logic goes. If the Feds are investigating a murder in Los Angeles, can they just clean the hard drive of every LA Times reporter who may have gotten a tip?