Snap Shot
- The question: How does the time between an event and an interview, identification, or trial affect what a witness, complainant, or accused can accurately report?
- What the research shows: Delay generally reduces how much is reported more than its accuracy, and central, well-encoded information lasts longest. Discussion, media exposure, and repeated interviews during the delay shape the later account. New details in later interviews are often accurate, delay weakens face memory, and many people first disclose child sexual abuse years later and remember it into adulthood.
- What it does not show: Research cannot say how much a particular witness has forgotten or whether a late-reported detail is accurate. A fuller, more confident account after a long delay is not thereby more accurate, and an inconsistent or delayed account is not thereby unreliable.
- The law: Statutes of limitation are the primary protection against stale charges, and a due process challenge to pre-accusation delay generally requires actual prejudice and also weighs the reasons for the delay (Marion, Lovasco; Art. 43, UCMJ; A.R.S. § 13-107); Arizona requires intentional delay for tactical advantage or harassment plus actual prejudice (Broughton; Lacy). Delay is a Biggers identification factor, and expert testimony is governed by Rule 702, Houser, Chapple, and Nordstrom.
- Issues for each side: Prosecutors can show that delayed accounts and later-added details are often accurate and that delayed disclosure is common, without treating detail or confidence as corroboration; defense counsel can tie loss and change to the specific intervals and intervening events in the case, without arguing that delayed memory is unreliable as a class.
Legal proceedings run on delay. A witness may be interviewed minutes after an event and testify a year later; a complainant may first disclose childhood abuse decades after it ended; a cold case may be charged when new forensic testing identifies a suspect long after the investigation stalled. Each interval raises the same questions: what is likely to have been lost, what is likely to have changed, and how the account at trial relates to earlier accounts.
This paper addresses the forensic consequences of delay; the mechanisms of forgetting are covered in the companion paper, Forgetting. It reviews changes in accounts over long intervals, repeated recall, identification after delay, delayed disclosure, and very old cases, followed by the law.
How Delay Changes an Account
Delay reduces what people report, generally more in completeness than in accuracy (Read & Connolly, 2007). The size of the loss varies widely. In studies Read and Connolly summarized, adults recalled about 43% fewer details of a filmed crime after three weeks than immediately (Turtle & Yuille, 1994), while other adult studies found little loss over a week; when adults and six-year-olds were questioned again five months after a staged demonstration, their accuracy on cued questions dropped from 71% to 62% for adults and from 66% to 38% for six-year-olds, although the amount of incorrect information did not increase (Flin et al., 1992). Gist is more durable than peripheral detail, but “peripheral” describes what mattered to the witness at the time, not to the case; a feature of a stranger’s appearance may have meant little then and be decisive later (Read & Connolly, 2007).
Real-world events show the same range. Witnesses to one shooting gave accounts judged about 80% accurate shortly afterward and about as accurate four to five months later, although accuracy was scored against a reconstruction drawn partly from their own first statements, while witnesses to a videotaped bank robbery gave strikingly inaccurate descriptions immediately (Read & Connolly, 2007).
What happens during a delay matters more than its length. Thinking about, discussing, and reading about an event can preserve memory while adding information from other sources (Read & Connolly, 2007). Accuracy-focused retelling can strengthen recall; slanted retelling, repeated suggestive questioning, or exposure to others’ accounts can contaminate it (see “Remembering Changes Memory”). Children who lived through Hurricane Andrew were interviewed a few months afterward, at ages three to four, and again six years later. All recalled the storm in vivid detail and reported more than twice as much information at the second interview; children in the most severely affected group were the most consistent across interviews (Fivush et al., 2004). Read and Connolly (2007) note that the later narratives contained many features absent from the first, whose accuracy could not be determined, and that the authors attributed the changes to reconstruction shaped by intervening discussion and the children’s current lives. An account can become richer over time without becoming more accurate, and it can also remain vivid and consistent about the core of a frightening event for years.
Repeated Recall: Reminiscence and Forgetting
Witnesses recall the same event many times, and each recall both reports and changes the memory. Across repeated free-recall attempts, the specific details vary and new details often appear, a pattern called reminiscence; in one study, repeated descriptions of a filmed crime produced new details each time, though not more than had been forgotten (Turtle & Yuille, 1994). Read and Connolly (2007) summarized the experimental work: cumulative correct recall usually rises with diminishing returns; the gains appear with free recall but not with specific or multiple-choice questions; new information carries some error, small in adults but larger in children and after long delays; and an early interview tends to protect against later loss. When six-year-olds were reinterviewed six months after an event, only 56% of the new information was correct (La Rooy et al., 2005, as summarized by Read & Connolly, 2007).
For adults interviewed properly, the research on new details is reassuring. Lane and Houston (2021, pp. 128–132) review evidence that reminiscent details are often highly accurate, citing a summary of 19 mock-crime studies (Fisher et al., 2009), and that an early, open-ended interview or self-administered written account reduces later forgetting without reducing accuracy. Consistency across accounts is only weakly related to overall accuracy (Brewer et al., 1999), and omissions are weaker signs of error than contradictions (Fisher et al., 2009). Mock jurors nevertheless discount reminiscent witnesses: in a 2026 study, a witness who testified to details omitted from a contemporaneous note was rated less credible, though verdicts did not differ, and expert testimony on memory raised the witness’s credibility ratings (Lin & Paterson, 2026).
Two cautions apply. Each retrieval strengthens what is retrieved, whether it is correct or mistaken, so consistency and confidence across retellings are not accuracy, and Read and Connolly (2007) recommend a small number of good, complete interviews conducted within a fairly short period. And a 2022 study reported that long retention intervals weakened the relationship between witnesses’ confidence and the accuracy of their recall (Spearing & Wade, 2022).
Delay and Eyewitness Identification
Memory for a once-seen face weakens with time. A meta-analysis of 53 studies found a reliable association between longer retention intervals and poorer face memory (r = .18, d = 0.37), equally strong for face-recognition and identification studies (Deffenbacher et al., 2008), consistent with an earlier meta-analysis (Shapiro & Penrod, 1986). In 271 actual police cases, the rate at which witnesses picked the police suspect from photographic lineups declined significantly with delay (Behrman & Davey, 2001), although archival data cannot show whether the suspect was guilty, and the decline may reflect weaker memory, more cautious witnesses, or more lineups without the culprit.
The first test matters most. Wixted and Mickes (2022) argue that a witness’s initial, properly conducted identification and the confidence expressed then are informative about accuracy, while later tests are contaminated by earlier ones. Because a lineup leaves a memory of the faces in it, including an innocent suspect’s, Wixted et al. (2021) recommend testing a witness’s memory of a suspect only once, noting that many witnesses who identified defendants confidently in court had earlier made low-confidence identifications or none. When an identification follows a long delay or earlier procedures, the record of the first test and its confidence statement is the best evidence of what the witness remembered (see Eyewitness Memory and Confidence and Accuracy).
Delayed Disclosure of Abuse
Many people who experienced child sexual abuse disclose it only after a long delay, and many have told no one for years. In a nationally representative Australian survey of 8,503 people aged 16 and older, almost half of those reporting child sexual abuse had never told anyone before; among those who had, about 46% first disclosed within a year, the median delay was one year and the mean 7.1 years, and 11.1% of disclosers aged 25 or older had waited more than 20 years (Mathews et al., 2025). In one sample of 204 Polish cases concluded between 2017 and 2023, conviction and acquittal were not associated with reporting delay but were associated with the thoroughness of the investigation (Lewulis, 2026); outcomes show how courts decided, not whether the accounts were accurate. The reasons for delay are addressed in the Child Abuse Allegations and Counterintuitive Testimony resources on this site.
For memory, the central point is that delayed disclosure is not delayed or recovered memory. Read and Connolly (2007) observe that most adults who report abuse from the distant past say they have remembered its core continuously; a small subset describe a period without memory, a contested phenomenon discussed in Recovered and Repressed Memory. When 175 people with documented child sexual abuse histories were later interviewed, 81% reported the documented abuse (Goodman et al., 2003), and in the same sample, accuracy 12 to 21 years after the abuse ended was higher among those for whom the abuse had greater traumatic impact (Alexander et al., 2005). Those studies also found memory errors, and nonreporting could reflect reluctance to disclose rather than absence of memory. For continuously remembered events, Read and Connolly expect the same strengths and frailties found over shorter intervals: durable memory for the core of a significant event, with loss of peripheral detail and vulnerability to reconstruction.
Cold Cases and Very Long Delays
Prosecutions of decades-old events, whether historic abuse or a homicide reopened by new forensic testing, rest on memory rehearsed, discussed, and sometimes publicized for years. Memory for a series of similar events becomes more general over time, so a person may remember what usually happened while struggling to attribute details to a specific occasion; and dating an event is a reconstruction from other knowledge unless it is tied to a landmark such as a move or a disaster (Read & Connolly, 2007). Because people incorporate outside information over long intervals, the original statements in the file, taken before media coverage and community discussion, are the best record of what each witness reported independently.
The early record matters equally for identifications. A witness who identifies a defendant decades later, after seeing the person in photographs, news coverage, or earlier procedures, is relying on a memory exposed to that face in other contexts (Wixted et al., 2021); conversely, an early statement or identification that matches later independent evidence can carry substantial weight.
Limits of the Evidence
Experimental studies of delay generally use filmed or staged events, students, and intervals of days to months; few test memory over years, and those that do usually lack an objective record. Field and archival studies have real events but rarely know the truth, and they often use consistency as a substitute for accuracy, although the two are only weakly related (Read & Connolly, 2007). Definitions of central and peripheral information, scoring, and single versus repeated testing differ across studies, so figures from one study transfer poorly to another. Above all, group findings cannot establish how much a particular witness has forgotten, whether a particular detail is accurate, or whether a delayed account is true.
Questions to Ask About This Research
When the figure that adults recalled about 43% fewer details after three weeks (Turtle & Yuille, 1994) is cited, counsel should ask what was counted: the number of details recalled from a filmed crime, not their accuracy, and other studies found smaller losses. When reminiscence research (Fisher et al., 2009; Lane & Houston, 2021) is offered to show that a new detail is reliable, counsel should ask whether it applies to this person, since the supportive findings come from adults interviewed without suggestive questioning, and La Rooy et al. (2005) found more error in information children added after a long delay. When Deffenbacher et al. (2008) is cited to estimate how much a witness’s memory weakened, counsel should ask whether that conclusion follows from a group-level function fitted to laboratory data. When Mathews et al. (2025) is cited, counsel should ask who was studied: a population survey describes how often and how late people disclose, not whether a particular disclosure is accurate. These questions are explained in “Reading Research Claims: A Guide for Attorneys” on this site.
Delayed Recall and the Law
Federal and Military Standards
The Supreme Court has treated statutes of limitation as the primary guarantee against overly stale charges and held that the Sixth Amendment speedy-trial right attaches only on arrest or formal charge (United States v. Marion, 1971). Before then, due process gives limited protection: Marion indicated that dismissal would be required if pre-indictment delay caused substantial prejudice and was an intentional device to gain tactical advantage, and United States v. Lovasco (1977) held that actual prejudice is necessary but not sufficient, that the reasons for delay must be weighed, and that investigative delay does not violate due process even if the defense is somewhat prejudiced. After the right attaches, courts weigh the length of and reasons for delay, the defendant’s assertion of the right, and prejudice, which includes defense witnesses’ inability to recall distant events accurately (Barker v. Wingo, 1972). The general federal limitation period is five years (18 U.S.C. § 3282); there is none for felonies under chapters 109A, 110 (with exceptions), and 117 of Title 18, under § 1591, or for kidnapping a minor (18 U.S.C. § 3299), and other child sexual or physical abuse offenses may be prosecuted during the life of the child or for ten years, whichever is longer (18 U.S.C. § 3283).
Under Article 43, UCMJ, most offenses cannot be tried unless sworn charges are received by an officer exercising summary court-martial jurisdiction within five years (10 U.S.C. § 843(b)(1)); murder, rape and sexual assault, including of a child, and certain other offenses may be tried at any time (§ 843(a)); and other child abuse offenses may be tried if sworn charges are received during the life of the child or within ten years, whichever is longer (§ 843(b)(2)). Earlier versions govern some older offenses. Rule for Courts-Martial 707 generally requires that the accused be brought to trial within 120 days after the earlier of preferral of charges, imposition of specified pretrial restraint, or entry on active duty, subject to excludable delay; delay before preferral or restraint is not counted under the rule. The time between crime and identification is a reliability factor under Neil v. Biggers (1972) and Manson v. Brathwaite (1977), and Military Rule of Evidence 321 treats an identification process as unlawful if it is so suggestive as to create a substantial likelihood of misidentification. Expert testimony is governed by Federal Rule of Evidence 702, as amended December 1, 2023 (the proponent must show it is more likely than not that the requirements are met), with gatekeeping under Daubert v. Merrell Dow Pharmaceuticals, Inc. (1993) extended by Kumho Tire Co. v. Carmichael (1999) to all expert testimony, including technical or other specialized knowledge. Military Rule of Evidence 702 tracks the federal rule; the Joint Service Committee’s 2025 compilation reflects the 2023 amendment under Military Rule of Evidence 1102 (Joint Service Committee on Military Justice, 2025), and military judges apply United States v. Houser (1993).
Arizona
Under A.R.S. § 13-107(A), prosecution for listed offenses, including any class 2 felony in chapter 14 (sexual offenses) or chapter 35.1 (sexual exploitation of children) of Title 13, may be commenced at any time; for other felonies the period runs from actual or reasonably diligent discovery by the State (§ 13-107(B)). In Arizona, a defendant claiming a due process violation from pre-indictment delay must show that the prosecution intentionally delayed proceedings to gain a tactical advantage or to harass the defendant and that the delay caused actual prejudice (State v. Broughton, 1988; State v. Lacy, 1996); diminished witness recollection alone has not been treated as substantial prejudice (Broughton). Practitioners should confirm current authority. Arizona Rule of Evidence 702 adopted the Daubert standard in 2012 and was amended effective January 1, 2024, to conform to the 2023 federal amendment (Ariz. Sup. Ct. Order R-23-0004).
Delay figured directly in State v. Chapple (1983), Arizona’s leading case on eyewitness expert testimony, which held it an abuse of discretion to exclude a qualified expert where the case rested on identifications made more than a year after the crime by witnesses whose earlier identifications had been inconsistent; the court limited the holding to its facts and barred opinions on whether a particular witness is right. State v. Nordstrom (2001) upheld limiting an expert to general factors, and experts may not opine on credibility (State v. Lindsey, 1986, 149 Ariz. at 475). Arizona’s identification instruction lists the time between the crime and the pretrial identification as a factor (Rev. Ariz. Jury Instr. (Crim.) Standard 45), and challenged pretrial identifications are examined at a Dessureault hearing (State v. Dessureault, 1969).
Special Issues in Legal Practice
The principles described above apply with equal force to every party in a legal proceeding. The science operates the same way regardless of who is asking the questions, and the research summarized here does not by itself favor either side. What differs between the parties is not the science but the vantage point — the particular places where these issues tend to surface, and the particular errors each party is best positioned to guard against. The two summaries below identify those recurring issues. They are offered for orientation, not as litigation strategy; in every case the controlling question is what the evidence in that case will, and will not, support, and the expert’s role is to inform the trier of fact rather than to advocate for either side.
Special Issues for Prosecutors
The research supports several propositions prosecutors can legitimately present. Delay reduces how much is reported more than the accuracy of what is reported, and memory for the core of a significant event can last for years. New details in later, properly conducted interviews of adults are often accurate, and omission is a weak indicator of inaccuracy. Delayed disclosure of child sexual abuse is common, most people with documented abuse histories remember it as adults, and in one recent sample delay was not associated with case outcome. Prosecutors are well positioned to preserve delayed evidence by producing the earliest statements and identification records, documenting what each witness was exposed to in the interval, and limiting repeated interviews and identification procedures.
The research also counsels caution. An account that has grown fuller and more confident is not thereby more accurate, and details first reported after media coverage, discussion, or repeated interviewing may come from those sources. Confidence expressed long after an event, and identifications made after earlier procedures or in court, are less informative than the first properly conducted test. Testimony that presents delayed disclosure research as showing that a particular delayed account is accurate goes beyond what the research shows.
Special Issues for Defense
The research supports several propositions defense counsel can legitimately present. Peripheral details, which can include the very features that would identify a stranger, are lost faster than gist, face memory weakens with time, and information added after a long delay carries more error, especially for children. Rehearsal, discussion, media exposure, and repeated interviews can reshape an account, and memory for repeated events becomes more general, so attribution of details to occasions and dating are reconstructions. The law recognizes dimmed memory as prejudice, and expert testimony linking the intervals and intervening events in a case to these findings is a legitimate way to help the factfinder.
The research also counsels caution about the limits that apply to the defense. Delayed memory is not unreliable as a class; central information can be durable, and later-added details are often accurate. Delayed disclosure is not recovered memory, and the contested recovered-memory literature does not apply to a continuously remembered event without a factual basis. An expert cannot say how much a particular witness has forgotten or that a detail is false. The same principles apply to the accused’s own recollection of distant events, including an alibi.
This paper is for educational purposes only and is not legal advice. The author is a psychologist, not an attorney; summaries of law are general and must be verified against current authority or with a licensed attorney.
References
Alexander, K. W., Quas, J. A., Goodman, G. S., Ghetti, S., Edelstein, R. S., Redlich, A. D., Cordon, I. M., & Jones, D. P. H. (2005). Traumatic impact predicts long-term memory for documented child sexual abuse. Psychological Science, 16(1), 33–40. https://doi.org/10.1111/j.0956-7976.2005.00777.x
Behrman, B. W., & Davey, S. L. (2001). Eyewitness identification in actual criminal cases: An archival analysis. Law and Human Behavior, 25(5), 475–491. https://doi.org/10.1023/A:1012840831846
Brewer, N., Potter, R., Fisher, R. P., Bond, N., & Luszcz, M. A. (1999). Beliefs and data on the relationship between consistency and accuracy of eyewitness testimony. Applied Cognitive Psychology, 13(4), 297–313. https://doi.org/10.1002/(SICI)1099-0720(199908)13:4<297::AID-ACP578>3.0.CO;2-S
Deffenbacher, K. A., Bornstein, B. H., McGorty, E. K., & Penrod, S. D. (2008). Forgetting the once-seen face: Estimating the strength of an eyewitness’s memory representation. Journal of Experimental Psychology: Applied, 14(2), 139–150. https://doi.org/10.1037/1076-898X.14.2.139
Fisher, R. P., Brewer, N., & Mitchell, G. (2009). The relation between consistency and accuracy of eyewitness testimony: Legal versus cognitive explanations. In R. Bull, T. Valentine, & T. Williamson (Eds.), Handbook of psychology of investigative interviewing (pp. 121–136). Wiley. https://doi.org/10.1002/9780470747599.ch8
Fivush, R., McDermott Sales, J., Goldberg, A., Bahrick, L., & Parker, J. (2004). Weathering the storm: Children’s long-term recall of Hurricane Andrew. Memory, 12(1), 104–118. https://doi.org/10.1080/09658210244000397
Flin, R., Boon, J., Knox, A., & Bull, R. (1992). The effect of a five-month delay on children’s and adults’ eyewitness memory. British Journal of Psychology, 83(3), 323–336. https://doi.org/10.1111/j.2044-8295.1992.tb02444.x
Goodman, G. S., Ghetti, S., Quas, J. A., Edelstein, R. S., Alexander, K. W., Redlich, A. D., Cordon, I. M., & Jones, D. P. H. (2003). A prospective study of memory for child sexual abuse: New findings relevant to the repressed-memory controversy. Psychological Science, 14(2), 113–118. https://doi.org/10.1111/1467-9280.01428
Joint Service Committee on Military Justice. (2025). Amendments to the Military Rules of Evidence since 1984 (G. E. Maggs, Ed.; 2025 ed.). https://jsc.defense.gov/Portals/99/MRE%20Amendments%202025.pdf
La Rooy, D., Pipe, M.-E., & Murray, J. E. (2005). Reminiscence and hypermnesia in children’s eyewitness memory. Journal of Experimental Child Psychology, 90(3), 235–254. https://doi.org/10.1016/j.jecp.2004.11.002
Lane, S. M., & Houston, K. A. (2021). Understanding eyewitness memory: Theory and applications. New York University Press.
Lewulis, P. (2026). Delayed reporting and legal outcomes in child sexual abuse cases: An empirical analysis. Child Abuse & Neglect, 173, Article 107892. https://doi.org/10.1016/j.chiabu.2026.107892
Lin, S., & Paterson, H. M. (2026). Contemporaneous notes and juror decision-making: Do reminiscence and expert testimony play a role? Psychiatry, Psychology and Law, 33(5), 1603–1625. https://doi.org/10.1080/13218719.2025.2568400
Mathews, B., Finkelhor, D., Malacova, E., Higgins, D. J., Collin-Vézina, D., & Do, H. P. (2025). Characteristics of first disclosure of child sexual abuse: Age, delay, recipient, and feeling of support. Child Abuse & Neglect, 170, Article 107803. https://doi.org/10.1016/j.chiabu.2025.107803
Read, J. D., & Connolly, D. A. (2007). The effects of delay on long-term memory for witnessed events. In M. P. Toglia, J. D. Read, D. F. Ross, & R. C. L. Lindsay (Eds.), The handbook of eyewitness psychology: Vol. 1. Memory for events (pp. 117–155). Lawrence Erlbaum Associates.
Shapiro, P. N., & Penrod, S. (1986). Meta-analysis of facial identification studies. Psychological Bulletin, 100(2), 139–156. https://doi.org/10.1037/0033-2909.100.2.139
Spearing, E. R., & Wade, K. A. (2022). Long retention intervals impair the confidence–accuracy relationship for eyewitness recall. Journal of Applied Research in Memory and Cognition, 11(3), 384–391. https://doi.org/10.1037/mac0000014
Turtle, J. W., & Yuille, J. C. (1994). Lost but not forgotten details: Repeated eyewitness recall leads to reminiscence but not hypermnesia. Journal of Applied Psychology, 79(2), 260–271. https://doi.org/10.1037/0021-9010.79.2.260
Wixted, J. T., & Mickes, L. (2022). Eyewitness memory is reliable, but the criminal justice system is not. Memory, 30(1), 67–72. https://doi.org/10.1080/09658211.2021.1974485
Wixted, J. T., Wells, G. L., Loftus, E. F., & Garrett, B. L. (2021). Test a witness’s memory of a suspect only once. Psychological Science in the Public Interest, 22(1_suppl), 1S–18S. https://doi.org/10.1177/15291006211026259
Legal Authorities
Barker v. Wingo, 407 U.S. 514 (1972).
Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993).
Kumho Tire Co. v. Carmichael, 526 U.S. 137 (1999).
Manson v. Brathwaite, 432 U.S. 98 (1977).
Neil v. Biggers, 409 U.S. 188 (1972).
State v. Broughton, 156 Ariz. 394, 752 P.2d 483 (1988).
State v. Chapple, 135 Ariz. 281, 660 P.2d 1208 (1983).
State v. Dessureault, 104 Ariz. 380, 453 P.2d 951 (1969).
State v. Lacy, 187 Ariz. 340, 929 P.2d 1288 (1996).
State v. Lindsey, 149 Ariz. 472, 720 P.2d 73 (1986).
State v. Nordstrom, 200 Ariz. 229, 25 P.3d 717 (2001).
United States v. Houser, 36 M.J. 392 (C.M.A. 1993).
United States v. Lovasco, 431 U.S. 783 (1977).
United States v. Marion, 404 U.S. 307 (1971).
U.S. Const. amends. V, VI.
10 U.S.C. § 843 (Article 43, Uniform Code of Military Justice).
18 U.S.C. § 3282.
18 U.S.C. § 3283.
18 U.S.C. § 3299.
Ariz. Rev. Stat. Ann. § 13-107.
Fed. R. Evid. 702.
Ariz. R. Evid. 702.
Ariz. Sup. Ct. Order R-23-0004 (2023).
Mil. R. Evid. 321.
Mil. R. Evid. 702.
Mil. R. Evid. 1102.
Rule for Courts-Martial 707.
Rev. Ariz. Jury Instr. (Crim.) Standard 45.
Related topic papers: Forgetting · Remembering Changes Memory · Confidence and Accuracy · Eyewitness Memory · Recovered and Repressed Memory · The Telescoping Effect
Related topics from Arizona Forensic Services: Child Abuse Allegations · Counterintuitive Testimony · Courts-Martial