Glenn Greenwald, the journalist who revealed National Security Agency surveillance leaks from former intelligence contractor Edward Snowden, dueled this week with former New York Times executive editor Bill Keller over objectivity in journalism. Keller argued that impartiality forces a journalist to test all assumptions. Greenwald, however, countered that impartiality didn’t test assumptions as much as confer authority to each of them. He explained that his new reporting venture, a website funded by eBay co-founder Pierre Omidyar, would treat official pronouncements with skepticism.