What Happened
Governance · Singapore · Explainerstatistics of 28 Apr 2026 · record to 27 Aug 2026
Executive summary · CPIB's own published figures
The Spark That Starts a Fire
Corruption leaves no complainant. The person who pays a bribe and the person who takes it both gain from it, so neither reports it — which is why Singapore's Corrupt Practices Investigation Bureau depends on being told by somebody else. In 2025, anonymous tip-offs supplied 56 of 160 corruption-related reports (35%) and 16 of 68 registered cases (24%), on CPIB's own published figures.
By the Numbers Singapore · calendar 2025
- 35%of 2025's 160 corruption-related reports were anonymous — 56 of them
- 24%of the 68 cases registered for investigation began with an anonymous tip — 16
- 68cases registered in 2025 — the lowest of the five years CPIB's own published chart covers
- 86%clearance rate in 2025 — the share of subjects investigated on which CPIB completed its inquiry
Three Numbers, Three Denominators not interchangeable
| Measure | 2025 | What it actually counts |
|---|---|---|
| Reports received | 160 | Everything arriving by email, hotline, website or letter. |
| Cases registered | 68 | The pursuable subset — decided within 14 days of receipt. |
| Persons prosecuted | 90 | Individuals charged that year; 84 of them from the private sector. |
Timeline
Turning Points 1952 → 2026
- 1952CPIB is established, replacing the Criminal Investigation Department's Anti-Corruption Branch after its failed investigation into a police-linked opium heist.
- 1960The Prevention of Corruption Act comes into force, giving CPIB its statutory powers and penalties.
- 1975Wee Toon Boon, Minister of State for the Environment, is charged with corruption and later convicted — the last minister charged before Iswaran.
- 1986Teh Cheang Wan, Minister for National Development, is investigated for corruption and dies before he can be charged.
- 1989The Complaints Evaluation Committee is set up — the body that still decides, within 14 days, whether a report is pursuable.
- 18 Jan 2024Transport Minister S. Iswaran is charged with 27 offences — the first minister charged since 1975.
- 25 Sep 2024The Attorney-General's Chambers amends Iswaran's two corruption charges to lesser Penal Code charges, citing the difficulty of proving intent when both parties to a bribe have reason to deny it; he pleads guilty.
- 3 Oct 2024Iswaran is sentenced to 12 months' imprisonment.
- Jun 2025Iswaran completes his sentence, the final months served under home detention.
- 19 Aug 2025CPIB charges nine individuals over alleged match-fixing in the 2025 K. Star National Basketball League.
- 10 Feb 2026Transparency International publishes its 2025 Corruption Perceptions Index: Singapore 3rd of 182, score 84.
- 28 Apr 2026CPIB publishes its 2025 annual statistics: 160 reports, 68 cases — both down for a fourth straight year.
The Argument
Who Is Being Told CPIB · inside the Prime Minister's Office
The Corrupt Practices Investigation Bureau replaced the police's own Anti-Corruption Branch in 1952, after that branch failed to make headway against three of its own detectives implicated in an opium heist, and has operated under the Prevention of Corruption Act since 1960. It sits inside the Prime Minister's Office and its Director reports to the Prime Minister — an arrangement that invites the obvious objection, and the Constitution answers it: under Article 22G, a Director refused consent by the Prime Minister may proceed anyway if the President, acting in his own discretion, concurs. The Act reaches both the public and the private sector with no exemption for rank or office, covers favours as well as cash, and follows Singapore citizens abroad. In practice the private sector dominates the caseload; CPIB names construction, manufacturing, and transport and storage as its most vulnerable industries.
- Art. 22Gthe President may let an investigation proceed the PM has refused
- S$100kmaximum fine per count — or 5 years' jail, 7 on government contracts
- Constructionone of three sectors CPIB names as most vulnerable
The Protection Has Two Exits strong, but not absolute
| Dimension | What holds | What strains |
|---|---|---|
| Anonymity | Section 36 shields the informer's identity even at trial. | A court may unmask an informer who lied — or where justice cannot otherwise be done. Honest informants are not categorically safe. |
| The filter | A 14-day pursuability test keeps an open channel usable. | A tip too vague to act on ends there — and anonymity leaves no way to go back and ask for more. |
| Deterrence | Knowingly giving false information to CPIB is itself an offence — a fine up to S$10,000 or a year's imprisonment. | The same section protects an honest but mistaken report — only a wilful false statement loses its protection. |
| Proof | Powers over bank accounts, bankers' books, search and seizure. | Even a fully resourced case can lose this fight: prosecutors dropped the two corruption charges against a former Cabinet minister in 2024, citing exactly this difficulty. |
What Others Add
From Tip-Off to Case prose left · thresholds right
Every complaint goes to the Complaints Evaluation Committee, set up in 1989, which decides within 14 days whether it falls inside CPIB's purview and carries enough to act on — identities, amounts, date, time, place, mode of transaction, and the favour given in return. The test is not certainty but pursuability. A report that is not registered has not thereby been found false: it may be referred to another agency, or sent to a public officer's own department for disciplinary action. Traffic runs the other way too — CPIB says its own intelligence work has lifted thin reports into live cases.
- 14 daysto decide whether a complaint is pursuable
- 1989the Complaints Evaluation Committee is set up
Four Years of Reports and Cases 2022 → 2025
| Year | Reports | Anonymous | Cases | From anonymous |
|---|---|---|---|---|
| 2022 | 234 | 100 · 43% | 83 | 13 · 16% |
| 2023 | 215 | 98 · 46% | 81 | 20 · 25% |
| 2024 | 177 | 61 · 34% | 75 | 17 · 23% |
| 2025 | 160 | 56 · 35% | 68 | 16 · 24% |
Read along the rows and the shape is not a straight line. The anonymous share of reports rose from 43% in 2022 to 46% in 2023, then stepped down to 34–35% in 2024–2025. What moves in one direction every year is the rate at which an anonymous tip becomes a case: 13% in 2022, 20% in 2023, 28% in 2024, 29% in 2025. Reports overall convert at a rising rate too, 36% to 43% — anonymous tips still convert less often than named ones in every year measured, but the gap has narrowed from 23 points to 14. This is an inference from the series, not a claim CPIB makes, and the data cannot separate better self-selection by informants from CPIB's own improved handling of thin leads.
- 13% → 29%anonymous-tip-to-case conversion rate, 2022 to 2025
- 23pt → 14ptgap between the anonymous and overall conversion rates, narrowing
International Standing Transparency International · 2025
Singapore scored 84 of 100 on Transparency International's 2025 Corruption Perceptions Index, ranking third of 182 countries and territories — unchanged from 2024. The index measures perceived levels of public-sector corruption, not corruption itself, drawn from 13 expert and business surveys; Transparency International's own release adds a caveat worth carrying alongside the score: Singapore and Switzerland are “among the top scorers, but have faced scrutiny for facilitating the movement of dirty money” — a high score is not a claim that a country enables no corruption anywhere in the world, only that its own public sector is perceived as clean.
- 3rd / 182Singapore's rank on the 2025 TI Corruption Perceptions Index, score 84
- perceptionswhat the index measures — not a count of corruption itself
Conclusion
What the Numbers Can and Cannot Say outcomes · 2025
- 84/90of those prosecuted in 2025 came from the private sector
- 3rdof 182 on Transparency International's 2025 index, score 84
- 98%rate Singapore's corruption situation good, very good or excellent — CPIB's own 2025 survey
- 29%of 2025's anonymous tips became a registered case — up from 13% in 2022
Bottom line
CPIB cannot see corruption unless someone tells it. Anonymity is the mechanism that makes telling survivable, and the 14-day pursuability test is what keeps the channel useful rather than merely open. In 2025 that combination produced 16 investigations that began with a tip nobody was obliged to give.
The unresolved question
Reports have fallen four years running, and CPIB's own figures cannot distinguish less corruption from less reporting. A steady index score of 84 and 98% rating the corruption situation good or better are the best evidence for the benign reading — evidence, not proof, and Transparency International's own caution that a high score is not a guarantee applies here too.
How to Read These Numbers four rules
- Name the denominator — 35% is of reports received, 24% is of cases registered.
- Don't read "not registered" as "untrue" — a report may be referred onward or handled departmentally.
- Treat a falling count as ambiguous — fewer reports fits less corruption and less reporting alike.
- Share and conversion are different measures — the anonymous share of reports rose before it fell, but the rate an anonymous tip becomes a case has risen every year since 2022.