ProPublica is a nonprofit newsroom that investigates abuses of power. Sign up to receive our biggest stories as soon as they’re published. This story was reported in collaboration with the Tow Center for Digital Journalism at Columbia Journalism School. Reporting Highlights Deceptive Political Ads: Eight deceptive advertising networks have placed over 160,000 election and social issues ads across more than 340 Facebook pages in English and Spanish. Harmed Users: Some of the people who clicked ...