A false accusation of rape is the intentional reporting of a rape where no rape has occurred. It is difficult to assess the prevalence of false accusations because they are often conflated with non-prosecuted cases under the designation "unfounded". However, in the United States, the FBI Uniform Crime Report in 1996 and the United States Department of Justice in 1997 reported that 8% of accusations for forcible rape had been through investigation determined to be false. Studies in other countries have reported their own rates at anywhere from 1.5% (Denmark) to 2–4% (Canada). Due to varying definitions of a "false accusation", the true percentage remains unknown.
Estimates of prevalence
It is extremely difficult to assess the prevalence of false accusations. Not all jurisdictions have a distinct classification of false accusation, resulting in these cases being combined with other types of cases (e.g. where the accuser did not physically resist the suspect or sustain injuries) under headings such as "unfounded" or "unproved". There are many reasons other than falsity that can result in a rape case being closed as unfounded or unproven. DiCanio (1993) states that while researchers and prosecutors do not agree on the exact percentage of false allegations, they generally agree on a range of 2% to 10%.
Crown Prosecution Service report (2011–2012)
A report by the Crown Prosecution Service (CPS) examined rape allegations in England and Wales over a 17-month period between January 2011 and May 2012. It showed that in 35 cases authorities prosecuted a person for making a false allegation, while they brought 5,651 prosecutions for rape. Keir Starmer, the head of the CPS, said that the "mere fact that someone did not pursue a complaint or retracted it, is not of itself evidence that it was false" and that it is a "misplaced belief" that false accusations of rape are commonplace. He added that the report also showed that a significant number of false allegations of rape (and domestic violence) "involved young, often vulnerable people. About half of the cases involved people aged 21 years old and under, and some involved people with mental health difficulties. In some cases, the person alleged to have made the false report had undoubtedly been the victim of some kind of offence, even if not the one that he or she had reported."
David Lisak's study, published in 2010 in Violence Against Women, classified as demonstrably false 8 out of the 136 (5.9%) reported rapes at an American university over a ten-year period.Applying IACP guidelines, a case was classified as a false report if there was evidence that a thorough investigation was pursued and that the investigation had yielded evidence that the reported sexual assault had in fact not occurred. A thorough investigation would involve, potentially, multiple interviews of the alleged perpetrator, the victim, and other witnesses, and where applicable, the collection of other forensic evidence (e.g., medical records, security camera records). For example, if key elements of a victim's account of an assault were internally inconsistent and directly contradicted by multiple witnesses and if the victim then altered those key elements of his or her account, investigators might conclude that the report was false. That conclusion would have been based not on a single interview, or on intuitions about the credibility of the victim, but on a "preponderance" of evidence gathered over the course of a thorough investigation."
Police in Victoria, Australia (2006)
A study of 850 rape accusations made to police in Victoria Australia between 2000 and 2003 found that 2.1% were ultimately classified by police as false, with the complainants then charged or threatened with charges for filing a false police report.
A 2006 paper by Philip N.S. Rumney in the Cambridge Law Journal offers a review of studies of false reporting in the US, New Zealand and the UK. Rumney draws two conclusions from his review of literature. First, the police continue to misapply the "no-crime" or "unfounding" criteria. Studies by Kelly et al. (2005), Lea et al. (2003), HMCPSI/HMIC (2002), Harris and Grace (1999), Smith (1989), and others found that police decisions to no-crime were frequently dubious and based entirely on the officer's personal judgment. Rumney notes that some officers seem to "have fixed views and expectations about how genuine rape victims should react to their victimization". He adds that "qualitative research also suggests that some officers continue to exhibit an unjustified scepticism of rape complainants, while others interpret such things as lack of evidence or complaint withdrawal as 'proof' of a false allegation".
Rumney's second conclusion is that it is impossible to "discern with any degree of certainty the actual rate of false allegations" because many of the studies of false allegations have adopted unreliable or untested research methodologies. He argues, for instance, that in addition to their small sample size, the studies by Maclean (1979) and Stewart (1981) used questionable criteria to judge an allegation to be false. MacLean deemed reports "false" if, for instance, the victim did not appear "dishevelled" and Stewart, in one instance, considered a case disproved, stating that "it was totally impossible to have removed her extremely tight undergarments from her extremely large body against her will".
British Home Office study (2005)
A 2005 study, "A gap or a chasm? Attrition in reported rape cases" was the largest and most rigorous study to date commissioned by the British Home Office on UK rape crime, from the initial reporting of a rape through to legal prosecutions. The study was based on 2,643 sexual assault cases (Kelly, Lovett, and Regan, 2005). Of these, police departments classified 8% as false reports.
The researchers noted that some of these classifications were based simply on the personal judgments of the police investigators and were made in violation of official criteria for establishing a false allegation. Closer analysis of this category applying the Home Office counting rules for establishing a false allegation and excluding cases where the application of the cases where confirmation of the designation was uncertain reduced the percentage of false reports to 3%. The researchers concluded that "one cannot take all police designations at face value" and that "[t]here is an over-estimation of the scale of false allegations by both police officers and prosecutors." Moreover, they added:
The interviews with police officers and complainants' responses show that despite the focus on victim care, a culture of suspicion remains within the police, even amongst some of those who are specialists in rape investigations. There is also a tendency to conflate false allegations with retractions and withdrawals, as if in all such cases no sexual assault occurred. This reproduces an investigative culture in which elements that might permit a designation of a false complaint are emphasised (later sections reveal how this also feeds into withdrawals and designation of 'insufficient evidence'), at the expense of a careful investigation, in which the evidence collected is evaluated.
FBI reports from 1996 consistently put the number of "unfounded" rape accusations around 8%. In contrast, the average rate of unfounded reports for "Index crimes" tracked by the FBI is 2%. This estimate was criticised as meaningless by academic Bruce Gross:
Many of the jurisdictions from which the FBI collects data on crime use different definitions of, or criteria for, "unfounded." That is, a report of rape might be classified as unfounded (rather than as forcible rape) if the alleged victim did not try to fight off the suspect, if the alleged perpetrator did not use physical force or a weapon of some sort, if the alleged victim did not sustain any physical injuries, or if the alleged victim and the accused had a prior sexual relationship. Similarly, a report might be deemed unfounded if there is no physical evidence or too many inconsistencies between the accuser's statement and what evidence does exist. As such, although some unfounded cases of rape may be false or fabricated, not all unfounded cases are false.
In 1994, Eugene J. Kanin of Purdue University investigated the incidences of false rape allegations made to the police in one small urban community in the Midwest United States (population 70,000) between 1978 and 1987. He states that unlike in many larger jurisdictions, this police department had the resources to "seriously record and pursue to closure all rape complaints, regardless of their merits". He further states each investigation "always involves a serious offer to polygraph the complainants and the suspects" and "the complainant must admit that no rape had occurred. She is the sole agent who can say that the rape charge is false".
The number of false rape allegations in the studied period was 45; this was 41% of the 109 total complaints filed in this period. The researchers verified, whenever possible, for all of the complainants who recanted their allegations, that their new account of the events matched the accused's version of events.
After reviewing the police files, Kanin categorized the false accusations into three broad motivations: alibis, revenge, and attention-seeking. These motivations were assigned prevalence of roughly 50%, 30%, and 20% respectively. This categorization was supported by the details of complainant recantations and other documentation of their cases.
Kanin also investigated the combined police records of two large Midwestern universities over a three-year period (1986–1988), and found that 50% of the reported forcible rapes were determined to be false accusations (32 of the total 64). No polygraphs were utilized, the investigations were the sole responsibility of a ranking female officer, and a rape charge was only counted as false under complainant recantation. In this sample, the motivations mentioned above were roughly evenly split between alibi and revenge, with only one case characterized as attention-seeking.
Critics of Kanin's report include David Lisak, an associate professor of psychology and director of the Men's Sexual Trauma Research Project at the University of Massachusetts Boston. He states, "Kanin's 1994 article on false allegations is a provocative opinion piece, but it is not a scientific study of the issue of false reporting of rape. It certainly should never be used to assert a scientific foundation for the frequency of false allegations."
According to Lisak, Kanin's study lacked any kind of systematic methodology and did not independently define a false report, instead recording as false any report which the police department classified as false. The department classified reports as false which the complainant later said were false, but Lisak points out that Kanin's study did not scrutinize the police's processes or employ independent checkers to protect results from bias.
Kanin, Lisak writes, took his data from a police department which used investigation procedures (polygraphs) that are discouraged by the U.S. Justice Department and denounced by the International Association of Chiefs of Police. These procedures include the "serious offer", in this department, of polygraph testing of complainants, which is viewed as a tactic of intimidation that leads victims to avoid the justice process and which, Lisak says, is "based on the misperception that a significant percentage of sexual assault reports are false." The police department's "biases...were then echoed in Kanin's unchallenged reporting of their findings." While also noting some of the same criticisms of Kanin, Rumney's 2006 metastudy of US and UK false rape allegation studies adds that "if, indeed, officers did abide by this policy then the 41% could, in fact, be an underestimate given the restrictive definition of false complaints offered by the police in this study. The reliability of these findings may be somewhat bolstered by the fact that the police appeared to record the details and circumstances of the fabrications."
Bruce Gross writes in the Forensic Examiner that Kanin's study is an example of the limitations of existing studies on false rape accusations. "Small sample sizes and non-representative samples preclude generalizability." Philip N.S. Rumney questions the reliability of Kanin's study stating that it "must be approached with caution". He argues that the study's most significant problem is Kanin's assumption "that police officers abided by departmental policy in only labeling as false those cases where the complainant admitted to fabrication. He does not consider that actual police practice, as other studies have shown, might have departed from guidelines."