To what extent can a professional writer write about factual events and people? For example, I am working on?

For example, I am working on a piece that will include sports news events in some detail that will include events like Tiger Woods, Ben Rothlisberger scandals, New York Yankees winning the World Series, Alabama Crimson Tide winning the BCS title game, Duke winning the National Championship. I am wondering to what extent I can write about people and teams. I realize they do have to be factual. The events and people are not going to be central to the story but they will be used in the story's environment.