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United KingdomPublic sector2025 – ongoing

HM Prison and Probation Service

Automated quality scoring of Key Work session notes

HMPPS used machine learning to score around 80,000 prison case notes monthly

In progressCompany's own claimOfficial ↗

Problem

Manual reviews covered only a sample of Key Work session notes. The sample supported annual prison comparisons but could not reliably track monthly changes.

Approach

The Ministry of Justice built a pipeline that removed names with BERT, represented text with Longformer and predicted quality with gradient boosting. Data scientists ran it monthly and uploaded scores to the HMPPS Performance Hub. Prison managers used the scores for quality reviews, with human reassessment available when prisons challenged a score.

Results

around 80,000case notes scored monthly, according to HMPPSCompany's own claim[1]

Takeaway

The system expanded assessment beyond sampled notes. Its scores measured documented session quality, rather than rehabilitation outcomes.

Categories

Business function
Production and quality
Innovation type
Process innovation
Evidence
Company's own claim

Sources

  1. HMPPS: Key Work quality assurance automation
    GOV.UK25 Sep 2025Company publication

Source summaries

[1]GOV.UK25 Sep 2025

HMPPS described automated scoring of around 80,000 notes each month. It explained the text-processing models and how prisons could request human reassessment.

Full details are in the original sources.

Added 1 Nov 2026 · Updated 1 Nov 2026
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