Google’s Gmail favors left-wing candidates, sends far more emails from conservatives to spam: study

A new study found that Google’s Gmail favors liberal candidates, allowing the vast majority of emails from left-wing politicians to land in the user’s inbox while more than two-thirds of messages from conservative candidates are marked as spam.

North Carolina State University’s Department of Computer Science published, "A Peek into the Political Biases in Email Spam Filtering Algorithms During US Election 2020," last week in order to determine if spam filtering algorithms (SFAs) are biased toward a particular political party or ideology. The extensive study took place over a course of five months, from July 1, 2020 to November 30, 2020 on Gmail, Outlook, and Yahoo. They created 102 email accounts and subscribed to two Presidential, 78 Senate, and 156 House candidates. 

"To accurately estimate the political biases and mitigate any potential effects of demographics (ethnicity, age, and gender), we created multiple email accounts with different combinations of demographic factors and designed two experiments. The first experiment studies the general trends of biases in SFAs across the email services for the Presidential, Senate and House candidates. The second experiment studies the impact of different email interactions such as reading the emails, marking them as spam, or vice versa on the biases in SFAs. We designed an automated process to perform all the subscriptions, and took periodic backups to keep all the email accounts active as well as to keep track of the correct number of spam emails received over the course of data collection for each of the three services," they wrote.