Peer-reviewed research on false rape accusation statistics consistently places the rate between 2% and 8% of reports made to law enforcement, with most studies clustering around 5% to 6%. That range has held steady across decades, jurisdictions, and research methods. The number that matters more than any single figure is the methodology behind it, because how researchers define “false” changes the count dramatically.
What the Major Studies Found
The most frequently cited study analyzed 136 sexual assaults reported to a major Northeastern university over ten years. Eight of those reports — 5.9% — met the researchers’ criteria for a false allegation.1SAGE Journals. False Allegations of Sexual Assault: An Analysis of Ten Years of Reported Cases
A larger multi-site study of eight U.S. communities examined 2,059 sexual assault reports received by law enforcement over an 18-to-24-month window. About 7% — 140 reports — were classified as false. That study built in ongoing training for participating agencies to ensure consistent definitions, plus random checks for data entry errors, making it one of the more controlled datasets available.
Other research lands in the same neighborhood. An analysis of sexual assault cases reported to the Los Angeles Police Department in 2008 found a 4.5% false report rate. In an international comparison, British police initially classified 8% of 2,643 sexual assault reports as false, but when researchers applied strict evidentiary criteria for what actually counts as a fabrication, the number dropped to 2%.
That gap between the police classification and the researchers’ classification is the heart of why estimates vary. Departments using loose definitions push numbers toward the high end. Researchers applying rigorous standards pull them toward the low end. The range still lands between 2% and 8%.
Why “Unfounded” Doesn’t Mean “False”
In statistics on false reports, the word “unfounded” comes up constantly, and it means something specific. In the FBI’s crime reporting system, an unfounded complaint is one that is “false or baseless.”2Federal Bureau of Investigation. Uniform Crime Reporting Handbook When investigators unfound a report, it gets subtracted from the count of actual offenses in national crime databases.3U.S. Department of Education. Unfounded Crimes Only sworn law enforcement personnel can make that determination.
“Unfounded” lumps together two very different situations. A false report is one where the investigation establishes that no crime occurred or was attempted. A baseless report is one where the described incident doesn’t meet the legal elements of a crime, though the person filing may be telling the truth about what happened to them.
Professional guidelines from the International Association of Chiefs of Police make this distinction explicit. Those guidelines warn that none of the following should be treated as evidence of a false report on their own: insufficient evidence to prosecute, delayed reporting, a victim’s decision not to cooperate, or inconsistencies in a victim’s statement. Each is common in legitimate sexual assault cases. Departments that conflate “hard to prove” with “didn’t happen” inflate their unfounded numbers.
Why Rates Differ Between Jurisdictions
A department in one city might report a 2% unfounded rate while a neighboring jurisdiction shows 15%, and neither number is necessarily wrong. They’re measuring different things. The FBI framework provides definitions, but individual officers and department policies determine how those definitions get applied.
A department that trains detectives to distinguish between “false” and “baseless” will produce lower unfounded numbers than one that treats them interchangeably. A department that only unfounds a case when the complainant recants will look different from one that unfounds based on an investigator’s judgment alone.
Budget matters too. A well-funded department that can devote significant investigative hours to each case will reach better-informed conclusions than one triaging a backlog. When an overworked detective can’t investigate thoroughly, cases sometimes get classified as unfounded simply because there isn’t enough evidence to move forward, even though that’s supposed to fall under a separate category. Record-keeping technology adds noise. Manual data entry, incompatible software systems, and inconsistent transmission to federal databases all introduce errors that compound across thousands of agencies. Comparing unfounded rates between jurisdictions without accounting for these differences reads more precision into the data than it contains.
How the Numbers Fit Against Unreported Assaults
No honest discussion of false report rates leaves out this context: the vast majority of sexual assaults never reach police. Research estimates that fewer than 5% of sexual assaults are reported to law enforcement.4PMC. Unfounded Sexual Assault: Women’s Experiences of Not Being Believed by the Police The Bureau of Justice Statistics consistently finds through its victimization surveys that sexual assault has one of the lowest reporting rates of any violent crime.
The math matters. If roughly 5% of sexual assaults get reported, and roughly 5% of those reports are false, then false reports represent about 0.25% of the total number of sexual assaults that actually occur. That fraction doesn’t minimize the damage a false accusation causes to the person targeted. It can be devastating. But it does put the phenomenon in proportion against the far more common outcome of an assault that is never reported at all.
Wrongful Convictions Tied to Sexual Assault Cases
The National Registry of Exonerations tracks every known case in the United States where a convicted person was later cleared. As of 2026, the Registry documents 3,793 exonerations across all crime types since 1989, representing more than 35,394 years of imprisonment served by innocent people.5National Registry of Exonerations. The National Registry of Exonerations Sexual assault cases make up a meaningful subset of those numbers, though the Registry does not publish a single headline percentage for that category.
Among DNA-based exonerations, where biological evidence definitively proved innocence, exonerees spent an average of 14 years in prison before their convictions were overturned. Eyewitness misidentification was the leading contributing factor, present in 62% of DNA exoneration cases. False confessions contributed to 29%.6Innocence Project. Our Impact: By the Numbers
For child sexual abuse cases specifically, a 2026 study analyzing 326 exonerations from the National Registry found that perjury or false accusation was the most frequent contributing factor, more common than in other crime categories.7PubMed. An Archival Analysis of 326 Child Sexual Abuse Cases From the National Registry of Exonerations
That distinction between adult and child sexual assault exonerations is worth noting. In adult cases, the most common cause of wrongful conviction is a stranger misidentifying the perpetrator: someone who genuinely experienced a crime but identified the wrong person. In child cases, the dynamics are different, with false or coerced testimony playing a larger role. Lumping all sexual assault exonerations together obscures those very different error patterns.
Criminal Penalties When a Report Is Proven False
Filing a false police report is a crime in every state. The classification and penalty vary, but most states treat it as a misdemeanor punishable by up to six months or a year in jail. Some states elevate the charge to a felony under certain circumstances, such as when the false report triggers a large-scale emergency response or leads to someone’s arrest.
At the federal level, making false statements to a federal investigator carries up to five years in prison. If the false statement relates to a sexual abuse offense, the maximum sentence increases to eight years.8Office of the Law Revision Counsel. 18 U.S. Code 1001 – Statements or Entries Generally Beyond the false report charge itself, a person who lies under oath during a legal proceeding faces separate perjury charges, which are felonies in every jurisdiction.
In practice, prosecutions for filing false sexual assault reports are relatively uncommon. Prosecutors worry that aggressive enforcement would deter legitimate victims from coming forward, and proving that a report was deliberately fabricated, rather than mistaken or simply unprovable, is itself a high evidentiary bar.