How have annual rates of sexual offences by non-UK nationals changed in the UK over the last decade (2015–2024)?

1. National totals rose; attribution to nationality is fragmented

ONS trend summaries show police‑recorded sexual offences increased markedly over the last decade (for example, nearly 189,000 sexual offences recorded in 2023/24) and survey estimates of prevalence are higher in 2025 than in 2015 (CSEW sexual assault prevalence 1.7% YE Mar 2015 vs 2.4% YE Mar 2025) ^{[2] [1]}. However, those national counts and survey measures do not break annual series down reliably by defendant nationality across the whole 2015–2024 period — available official outputs focus on victim characteristics, ethnicity or give snapshots rather than a continuous decade‑long nationality time series ^{[5] [6] [1]}.

2. Local FOIs show non‑UK nationals present in 2024 arrest/court activity, but they are not national trend series

Police force FOI releases, such as West Yorkshire Police’s February 2025 response, publish counts of arrests/charges for sexual offences where detainees self‑stated non‑UK nationality for calendar 2024; these are force‑level incident counts and represent arrests (not unique individuals, and not convictions) for the single year 2024 ^[3]. Such documents demonstrate that non‑UK nationals appear in arrest statistics, but they do not provide a consistent national time‑series from 2015–2024 ^[3].

3. MoJ/think‑tank FOI work paints a contested picture for 2024 convictions

Recent FOI‑based work cited in media and by independent groups gives specific percentages for 2024: the Centre for Migration Control and second‑stage analyses reported that foreign nationals made up between 15% and 34% of some sexual‑offence conviction categories in 2024, and one aggregation put foreign national convictions at about 1,118 known cases out of 7,874 total sexual‑offence convictions in 2024 (leading to estimates of 15–22% when accounting for “unknown” nationality cases) ^[4]. LBC reported a MoJ‑sourced FOI claim that foreign nationals accounted for 26% of 1,453 sexual assault convictions on women in a single recent year ^[7]. These figures are for 2024 and are subject to classification choices, unknowns and FOI limitations ^{[4] [7]}.

4. Important methodological limitations and contested interpretations

Multiple sources stress limits: police nationality data are self‑reported at arrest and may not equal legal citizenship; court/conviction counts differ from arrest/charge counts; there are substantial gaps between defendants prosecuted and convictions (e.g., 14,242 defendants proceeded against for sexual offences vs 8,098 convictions in 2024), and “unknown” nationalities complicate share calculations ^{[8] [4]}. The ONS cautions that rising police‑recorded sexual offences reflect recording and reporting changes as well as real prevalence shifts ^{[1] [9]}. Some media and watchdog pieces explicitly dispute headline claims about migrant responsibility for sexual offences, showing how different data slices (proceeded against vs convicted; local vs national; per‑capita rates vs raw counts) give divergent impressions ^{[8] [10]}.

5. Per‑capita and age‑adjusted comparisons exist but are disputed

Analyses that compute conviction rates per population (age‑adjusted or per‑100k) find foreign‑national conviction rates higher than British nationals in recent work — one age‑adjusted figure produced a rate of 3.01 per 100k versus 1.61 per 100k for British nationals (an 86% higher rate in that analysis) — but these methods and denominators (which census or population year to use) are debated and sensitive to “unknown” nationalities and to the time periods combined ^[4]. The Guardian and fact‑checking outlets have cautioned about exaggeration when commentators conflate different metrics or use short‑period FOI snapshots to make broader claims ^{[10] [8]}.

6. What can be stated for 2015–2024, and what is not found in current reporting

We can state confidently from ONS/MoJ‑sourced summaries that total police‑recorded sexual offences rose over the decade and that 2024 FOIs indicate non‑UK nationals are represented among arrests and convictions in 2024 ^{[2] [1] [3] [4]}. However, available sources do not publish a continuous, nationally consistent annual series of sexual‑offence rates specifically for non‑UK nationals covering 2015–2024; therefore a definitive year‑by‑year trend for non‑UK nationals across the whole decade is not present in the provided reporting ^{[5] [6] [3] [4]}.

7. How journalists, policymakers and researchers should proceed

To produce a robust decade trend you need: (a) consistent national data on defendants/convictions by legal nationality (not just self‑reported at arrest), (b) population denominators by nationality and age for each year to calculate per‑capita rates, and (c) transparent treatment of “unknown” nationalities and of the gap between arrests, prosecutions and convictions. Current public FOIs and analyses provide useful snapshots for 2024 but do not replace a harmonised ONS/MoJ series for 2015–2024 ^{[3] [4] [1]}. Available sources do not mention a single official national time‑series that meets those criteria ^{[5] [6]}.

If you want, I can: (a) draft a FOI request template aimed at MoJ/Met/ONS to obtain consistent yearly nationality breakdowns 2015–2024, or (b) collate the available FOI snapshots and compute provisional per‑capita comparisons for 2024 only, explicitly flagging methodological caveats.