By AMANDA POPE Staff reporter Mainstream newsrooms need to diversify coverage produced by “male and pale” newsrooms by giving activists the opportunity to write columns and air their opinions, Ryerson University journalism students were told during a recent panel discussion. The Ryerson Journalism Research Centre hosted the panel, “Activist, advocate, reporter, columnist: Where’s the line?” as a follow-up to controversy earlier this year over the extent to which writers for a news organization should become participants in news stories. Desmond Cole, who wrote a freelance column for the Toronto Star, disrupted a Police Services Board meeting in April to protest…