CIS executive director Mark Krikorian tweeted Tuesday that the social networking service had rejected paid promotion of a tweet after it was inexplicably tagged as "Hateful Content."
Later, the think tank put out a series of tweets criticizing the company's decision, and providing multiple examples showing that the phrase "illegal aliens" is a perfectly acceptable term in US legal practice.
In a press release released on Thursday, the CIS said four other tweets, including the phrases "illegal alien," or "criminal alien" and references to law enforcement, had been rejected by the Twitter Ads program recently using the same excuse.
In recent months, conservatives in the United States have accused the social media giant of double standards when it comes to its hateful conduct rules.