Courtroom Speech Recognition Accuracy Statistics (2026): 55+ Data Points on ASR Error Rates, Court Reporter Accuracy, and AI Transcription Pilots

Courtroom speech recognition accuracy statistics 2026: commercial ASR averaged a 35% word error rate for Black speakers vs 19% for white speakers, plus 50+ data points.

Five leading commercial speech recognition systems averaged a word error rate of 0.35 for Black speakers versus 0.19 for white speakers, and 23% of Black speakers’ audio produced transcripts too error-ridden to use, compared with just 1.6% for white speakers (Koenecke et al., PNAS 2020). Human transcription is not a clean benchmark either: certified Philadelphia court reporters transcribed African American English at 82.9% word accuracy, more than 12 points below the 95% standard they are certified at (Jones et al., Language 2019). Meanwhile, the people who produce the record are disappearing, with roughly 23,000 stenographers left after a 21% decade-long decline (AAERT, 2025 Court Reporting Industry Trends), and 71.3% of California’s family, probate, and civil hearings over three years had no verbatim record at all (Judicial Council of California, 2026). We aggregated data from PNAS, the Linguistic Society of America’s journal Language, the National Court Reporters Association, the Judicial Council of California, the Thomson Reuters Institute and National Center for State Courts, the Philippine Supreme Court, the UK Ministry of Justice, and peer-reviewed AI audits to show where courtroom transcription accuracy really stands in 2026. For the broader workforce picture, see our court reporting statistics.

TL;DR

  • Commercial ASR averaged a 0.35 word error rate for Black speakers vs 0.19 for white speakers (Koenecke et al., PNAS 2020).
  • 23% of Black speakers’ snippets vs 1.6% of white speakers’ snippets crossed the 0.5 WER threshold the authors treat as unusable (PNAS 2020).
  • Black men saw a 0.41 average WER, double the 0.21 rate for white men (PNAS 2020).
  • Philadelphia court reporters reached 82.9% word accuracy and 59.5% sentence accuracy on African American English (Jones et al., Language 2019).
  • 31% of court reporter transcriptions changed the who, what, when, where, or force of an utterance (Language 2019).
  • About 23,000 stenographers remain after a 21% ten-year decline; enrollment fell 74% (AAERT 2025).
  • NCRA newly certified members fell from 243 (2023) to 205 (2025); average court reporter age is 56 (NCRA Statistics, March 2026).
  • 72.4% of California’s Q1 2026 family, probate, and civil hearings had no verbatim record (Judicial Council of California 2026).
  • Only 17% of state courts use generative AI and 70% bar staff from AI tools (Thomson Reuters Institute 2025 State Courts Survey).
  • Philippine courts cut transcription time 50% on average, up to 80%, in an AI pilot (Supreme Court of the Philippines, 2025).
  • Roughly 1% of Whisper transcriptions contained hallucinated phrases, and 38% of those were harmful (Koenecke et al., ACM FAccT 2024).
  • A 15-member federal task force on courtroom speech-to-text was proposed in S. 4154 on March 19, 2026 (US Senate).

1. ASR Word Error Rates by Race, Dialect, and Gender

The core accuracy problem for courtroom speech recognition is not average performance but variance across speakers. Every one of the five systems tested made nearly twice as many errors for Black speakers as for white speakers, even on identical five-to-eight-word phrases, which points to the acoustic model rather than vocabulary. In a courtroom, where the record must be equally reliable for every witness, a tool that is accurate on average but unequal by speaker fails the basic test of fairness.

Most recent available data: Koenecke et al., Racial disparities in automated speech recognition, PNAS 2020. No study of comparable scale and design has been published since, which is itself a finding: the evidence base behind courtroom ASR procurement is six years old.

MetricValueSource
Average WER across 5 ASR systems, Black speakers0.35Koenecke et al., PNAS 2020
Average WER across 5 ASR systems, white speakers0.19Koenecke et al., PNAS 2020
Apple (worst performer) WER, Black vs white speakers0.45 vs 0.23Koenecke et al., PNAS 2020
Microsoft (best performer) WER, Black vs white speakers0.27 vs 0.15Koenecke et al., PNAS 2020
Average WER, Black men vs Black women0.41 vs 0.30Koenecke et al., PNAS 2020
Average WER, white men vs white women0.21 vs 0.17Koenecke et al., PNAS 2020
Snippets with WER above 0.5 (unusable), Black vs white speakers23% vs 1.6%Koenecke et al., PNAS 2020
WER on identical phrases, Microsoft, Black vs white speakers0.13 vs 0.07Koenecke et al., PNAS 2020

Context: the study matched 2,141 audio snippets from each group (19.8 hours from 73 Black and 42 white speakers). Median WER was 0.38 in Princeville, NC and 0.31 in Washington, DC, against 0.18 in Sacramento and 0.15 in Humboldt County, and error rates rose with the density of African American Vernacular English features. Vocabulary was not the cause: Google’s system had 98.7% of words spoken by Black participants in its vocabulary, versus 98.6% for white participants. As the Stanford Engineering summary notes, the authors specifically flagged criminal justice agencies transcribing courtroom proceedings as a setting where these gaps could cause harm.

Newer work confirms the mechanism without replacing the headline numbers. An Interspeech 2025 paper by Mojarad and Tang found a small but significant effect of consonant cluster reduction and ING-reduction on WER for African American English, and the Fair-Speech benchmark released in 2024 collected about 26.5K utterances from 593 US participants specifically to measure demographic fairness (Veliche et al., 2024). Readers comparing accuracy across tools can find general benchmarks in our speech-to-text statistics.

2. Human Court Reporter Accuracy on Dialect Speech

The fair comparison for courtroom ASR is not a perfect transcript but the human baseline, and that baseline is weaker than certification implies. Certified court reporters got 40.5% of African American English sentences wrong in some way, under better-than-courtroom conditions: a quiet room, high-quality audio, every utterance played twice, and unlimited time to revise. The gap between certification and real-world dialect performance is the single most underreported number in court transcription.

The study, Testifying while black (Jones, Kalbfeld, Hancock, and Clark, Language 2019), tested 27 court reporters working in the Philadelphia courts, roughly one third of the city’s official reporter pool, on 83 naturalistic utterances, yielding 2,241 transcriptions.

MetricValueSource
Certification accuracy standard for court reporters95% or 98%Jones et al., Language 2019
Average sentence-level transcription accuracy59.5%Jones et al., Language 2019
Best vs worst sentence-level accuracy77% vs 18%Jones et al., Language 2019
Average word-level accuracy82.9% (12.1 points below standard)Jones et al., Language 2019
Best vs worst word-level accuracy91.2% vs 58.4%Jones et al., Language 2019
Transcriptions that changed who, what, when, where, or force31% (701 of 2,241)Jones et al., Language 2019
Transcriptions that would have entered gibberish into the record11% (248)Jones et al., Language 2019
Average paraphrase (comprehension) accuracy33%Jones et al., Language 2019

Outlier note: in the pilot phase, lawyers who identified as African American English speakers reached 90% transcription accuracy, versus 64.2% for lawyers who spoke Standard American English. Black court reporters correctly paraphrased 52.5% of utterances versus 33.7% for nonblack reporters, and 70% of all participating reporters had never heard the term African American English. The lesson for AI procurement: a vendor that benchmarks only against Standard English test sets is measuring the wrong thing, and the same applies to human certification. We cover the parallel problem in employment in our accent bias statistics.

3. The Court Reporter Workforce Behind the Record

Accuracy debates matter more because the human supply is shrinking. New NCRA certifications fell for a second straight year, to 205 in 2025, while the average court reporter is now 56. Courts are not choosing between stenographers and software in the abstract; they are deciding what fills the seats that are already empty.

MetricValueSource
Certified stenographers remaining in the USAbout 23,000AAERT, 2025 Court Reporting Industry Trends
Decline in certified stenographers over the last decade21%AAERT, 2025 Court Reporting Industry Trends
Drop in stenography school enrollment (3,083 in 2015 to 790 in 2024)74%AAERT, 2025 Court Reporting Industry Trends
Stenography programs or schools closed over the decadeAbout 42%AAERT, 2025 Court Reporting Industry Trends
NCRA newly certified members, 2023 / 2024 / 2025243 / 211 / 205NCRA Statistics, March 2026
Average age of NCRA court reporter members56NCRA Statistics, March 2026
Court reporter and simultaneous captioner jobs, 202519,900BLS Occupational Outlook Handbook
Projected employment change, 2025-350% (about 1,800 openings a year)BLS Occupational Outlook Handbook

AAERT’s end-user survey (550+ respondents, fielded Q4 2024) quantifies the downstream effect: 76% report difficulty scheduling proceedings, 55% report higher costs, 39% report delays, and 26% say they are accepting lower-quality transcripts. And 96% named accuracy as the most significant performance indicator. Sources: AAERT industry report, NCRA Statistics, and the BLS court reporters profile, which explicitly expects AI transcription tools to limit future employment growth while reporters remain needed to review and edit digitally produced records. Caveat: AAERT represents electronic reporters and transcribers and commissioned the study, so its framing favors digital reporting even though its workforce figures draw on NCRA and BLS data.

4. Proceedings With No Verbatim Record at All

The worst transcription accuracy is no transcript. California, which restricts electronic recording in most case types, publishes the most detailed public data in the US on what happens when reporters are unavailable. Across three years, 3,007,651 hearings in family, probate, and unlimited civil cases proceeded with no verbatim record, which the state’s own fact sheet says will frequently be fatal to an appeal.

MetricValueSource
Hearings with no verbatim record, Q1 2026303,430 of 418,985 (72.4%)Judicial Council of California, 2026
Hearings with no verbatim record, Apr 2023 to Mar 20263,007,651 of 4,214,365 (71.3%)Judicial Council of California, 2026
Court-employed reporters vs additional FTE needed1,101 vs 458 moreJudicial Council of California, 2026
FTE reporters hired vs departed, Apr 2023 to Mar 2026381.8 vs 366.3 (net gain 15.5)Judicial Council of California, 2026
Share of new hires who were voice writers48.1% (183.5 FTE)Judicial Council of California, 2026
Decline in California licensees, FY 2013-14 to FY 2022-2320.9% (new applications down 42.9%)Judicial Council of California Fact Sheet, Jan 2025
California court spending on transcripts, FY 2023-24$23.7 millionJudicial Council of California Fact Sheet, Jan 2025
Private reporter cost per day, deposition vs trial$2,580 vs $3,300Judicial Council of California Fact Sheet, Jan 2025

Context: the pipeline is improving at the margin, with 176 new licenses issued in FY 2024-25 compared with 68 in 2022-23, and a 52.7% pass rate among 294 recent exam takers. But nearly half of new hires are voice writers, which is itself a speech-recognition workflow: the reporter re-speaks testimony into a mask-mounted microphone and software converts it. The live data sits on the Judicial Council’s shortage dashboard, and the cost figures come from its January 2025 fact sheet.

5. AI Transcription Adoption and Court Pilots

US state courts are cautious, and the numbers show a wide gap between expectations and permission. 91% of state court professionals expect AI to have at least a moderate impact on court operations, yet 70% say their court does not allow employees to use AI-based tools at all. The furthest-along deployments are outside the US, where national judiciaries can standardize on one platform.

MetricValueSource
State courts currently using generative AI17%Thomson Reuters Institute, 2025 State Courts Survey
Courts that do not allow employees to use AI-based tools70%Thomson Reuters Institute, 2025 State Courts Survey
Respondents rating AI as the most significant trend55%Thomson Reuters Institute, 2025 State Courts Survey
Court systems that have offered AI training25%NCSC, Preparing for Future Workforce Needs 2025
Respondents expecting staffing shortages to continue61%NCSC, Preparing for Future Workforce Needs 2025
Philippine AI transcription pilot scope (Jul 2023 to Sep 2024)Sandiganbayan + 41 trial courtsSupreme Court of the Philippines, 2025
Transcription time reduction in the Philippine pilot50% average, up to 80%Supreme Court of the Philippines, 2025
Reported accuracy over the course of the Philippine pilotImproved from 70% to 90-95%Supreme Court of the Philippines, 2025

The survey covered 443 state, county, and municipal court judges and professionals in March and April 2025 (Thomson Reuters Institute; NCSC summary). The Philippine results, presented by Chief Justice Alexander Gesmundo, came from the Scriptix platform with a custom Filipino and Taglish language model, and the Supreme Court authorized nationwide deployment in November 2024 (Supreme Court of the Philippines). Note that the starting accuracy of 70% would be unacceptable for any official record; the gains came from continued use and human editing, not from switching the tool on.

The UK offers the largest volume data point so far, though from probation rather than courtrooms: the Ministry of Justice reports that over 1,600,000 meetings were summarised with its in-house Justice Transcribe tool between October 7, 2025 and September 14, 2026, an illustrative saving of about 266,667 hours at 10 minutes per meeting (GOV.UK Justice Transcribe data). The department’s own announcement projects 18,750 calendar days freed each year, and HM Courts and Tribunals Service is now testing the same tool against contracted human transcribers for Crown Court transcripts. For how the wider legal sector is adopting AI, see our AI in legal statistics.

6. Hallucinations, Police Transcripts, and the Oversight Gap

Word error rate understates the legal risk of AI transcription, because a transcript can also contain words nobody said. 38% of Whisper’s hallucinated passages included explicit harms such as violence, false associations, or implied authority, the kind of content that could change how a judge or jury reads testimony. Courtroom audio is full of long pauses, and long non-vocal stretches are exactly what the researchers linked to hallucinations.

MetricValueSource
Whisper transcriptions with entirely hallucinated phrases or sentencesAbout 1% (1.4% on average)Koenecke et al., ACM FAccT 2024
Hallucinations containing at least one explicit harm38%Koenecke et al., ACM FAccT 2024
Hallucinations perpetuating violence19%Koenecke et al., ACM FAccT 2024
Hallucinations making inaccurate associations / implying false authority13% / 8%Koenecke et al., ACM FAccT 2024
Draft One AI police report trial: officers and reports85 officers, 755 reportsAdams et al., Journal of Experimental Criminology 2025
Draft One effect on report-writing timeNo statistically significant reductionAdams et al., Journal of Experimental Criminology 2025
Anchorage Police Department AI report trial length and result3 months, no significant time savingsAnchorage Police Department via EFF, 2025
Proposed federal task force on court speech-to-text15 members, report within 18 monthsS. 4154, Research and Oversight of AI in Courts Act of 2026

Context: the hallucination study (ACM FAccT 2024) found hallucinations occurred disproportionately for speakers with aphasia, who have longer non-vocal pauses. Body-camera audio already feeds the criminal record through AI-drafted police reports; the preregistered randomized trial of Axon Draft One (Springer) found no time saving because officers spent the gain editing out errors and adding missed facts, and the vendor had marketed a 50% reduction (EFF). The pending federal bill, introduced March 19, 2026, would require the task force to examine transcription accuracy, effects on speakers with accents or dialects, and watermarks for AI-modified records (S. 4154 text, GovInfo). The question for courts is no longer whether speech recognition is good enough on average; it is whether anyone is measuring it for the speakers who need an accurate record most.

Summary: Courtroom Speech Recognition Accuracy by the Numbers

MetricValueSource
Average ASR WER, Black vs white speakers0.35 vs 0.19Koenecke et al., PNAS 2020
Snippets with unusable transcripts (WER above 0.5), Black vs white23% vs 1.6%Koenecke et al., PNAS 2020
ASR WER, Black men vs white men0.41 vs 0.21Koenecke et al., PNAS 2020
Apple ASR WER, Black vs white speakers0.45 vs 0.23Koenecke et al., PNAS 2020
Court reporter word-level accuracy on African American English82.9%Jones et al., Language 2019
Court reporter sentence-level accuracy on African American English59.5%Jones et al., Language 2019
Court reporter transcriptions that changed meaning31%Jones et al., Language 2019
Court reporter certification standard95% to 98%Jones et al., Language 2019
US stenographers remainingAbout 23,000AAERT 2025
Stenography enrollment decline, 2015 to 202474%AAERT 2025
NCRA newly certified members, 2025205NCRA Statistics, March 2026
Average court reporter age56NCRA Statistics, March 2026
California hearings with no verbatim record, Apr 2023 to Mar 202671.3% (3,007,651)Judicial Council of California 2026
Additional court reporters California needs458 FTEJudicial Council of California 2026
State courts using generative AI17%Thomson Reuters Institute 2025
Courts barring staff from AI-based tools70%Thomson Reuters Institute 2025
Philippine AI pilot transcription time reduction50% average, up to 80%Supreme Court of the Philippines 2025
UK meetings summarised with Justice Transcribe, Oct 2025 to Sep 20261,600,000+UK Ministry of Justice 2026
Whisper hallucinations containing explicit harms38%Koenecke et al., ACM FAccT 2024

Methodology and Sources

Last updated: October 3, 2026. We update this roundup quarterly, and the next refresh is expected when the Judicial Council of California publishes its Q2 2026 court reporter shortage update and HMCTS reports results from its Justice Transcribe Crown Court transcript study.

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