NewsGuard: “Over the first seven months of Reality Gap Index reports — from June to December 2025 — NewsGuard found that an average of nearly half of Americans believed at least one false claim about major claims spreading in the news. For the first six months after the launch of the NewsGuard Reality Gap Index in June, the average percent of Americans who believed false claims was 50 percent. A dip in December reduced the average to 46 percent for the seven months of 2025. The monthly variations, of course, may have less to do with changes in Americans’ gullibility than with changes in the velocity, spread, and overall appeal of a particular false claim. For example, in July and August, when the Reality Gap Index reached a high of 64 percent, two particularly viral false claims dominated the news: that U.S. President Donald Trump declared martial law to address the crime problem in Washington D.C., and that Florida’s ‘Alligator Alcatraz’ immigrant detention center was surrounded by an alligator-infested moat.

• NewsGuard’s Reality Gap Index is the nation’s first ongoing measurement of Americans’ propensity to believe at least one of the top three false claims circulating online each month, sourced from NewsGuard’s False Claims Fingerprints data stream. Through a monthly survey of a representative sample of Americans conducted by YouGov, the Reality Gap Index measures the percentage of Americans who believe one or more of the month’s top three false claims…”