This story was originally published by Mother Jones and is reproduced here as part of the Climate Desk collaboration.
When protesters descended on Washington, D.C., last month for the March for Science, they carried signs that were straight to the point: “What do we want? Evidence-based science. When do we want it? After Peer Review.” And unlike the administration they were protesting, organizers were careful to apply scientific rigor to how they calculated the number of people who participated in the march.
As a result, it took organizers an unusually long time — three weeks — to come up with their estimate for how many people took part in the April 22 marches in Washington and 600 other cities worldwide. In a blog post published Monday, organizers approximated that nearly 1.1 million people had protested around the world, with the largest marches taking place in D.C. (100,000), San Francisco (50,000), Los Angeles (50,000), Chicago (60,000), and Boston (70,000).