New York University's Cybersecurity for Democracy (C4D) has released research that examines Facebook’s policy enforcement for political advertising - a key benchmark in its work to hold platforms to account. In collaboration with researchers with imec-DistriNet at KU Leuven in Belgium, a comprehensive audit of Facebook’s political ad detection and policy enforcement was conducted that examined 33.8 million Facebook ads that ran between July 2020 and February 2021. This time frame included elections in both the U.S. and Brazil and is the first known study to quantify the performance of Facebook’s political ad policy enforcement system at a large and representative scale. Notably, Facebook made the wrong decision for 83 percent of those ads that had not been declared as political by their advertisers and that Facebook or the researchers deemed political. In addition, Facebook missed a higher proportion of political ads outside the U.S
Here is a link to a summary of the findings, a link to a page with more detailed information, link to the full paper and a library of sample advertisements that were referenced.
