United Kingdom, 1945 to 2026

197 British stories where the official position changed

Food advice, NHS medicines and treatments, banned substances, scandals, court cases, secrets, laws and government promises, in ten parts.

This timeline is a starting catalogue. Unlike our fact-checked cases, each entry has not yet been checked against primary sources. Not every case involves dishonesty: many are honest changes as evidence improved.

The ten parts

• Food, farming and what Britain was told was safe: BSE, salmonella, trans fats, horsemeat and other food and farming stories where British official advice or rules changed.
• Food, farming and what Britain was told was safe: 20 cases
• NHS medicines that went from accepted to dangerous: Medicines used in Britain that were later withdrawn or restricted, from thalidomide to Vioxx and valproate.
• NHS medicines that went from accepted to dangerous: 20 cases
• British medical treatments and NHS advice later overturned: Treatments and NHS advice that changed as better evidence arrived, from bed rest and episiotomy to cot death advice.
• British medical treatments and NHS advice later overturned: 19 cases
• Poisonous substances Britain once allowed: Lead, asbestos, CFCs, PCBs, mercury and other substances once allowed in Britain and later banned or restricted.
• Poisonous substances Britain once allowed: 20 cases
• NHS scandals where official assurances were challenged: Infected blood, Gosport, Mid Staffs, maternity failures and other NHS scandals where official assurances were challenged.
• NHS scandals where official assurances were challenged: 20 cases
• Police, courts and the British justice system: Wrongful convictions, Hillsborough, the Post Office Horizon scandal and other failures in British policing and courts.
• Police, courts and the British justice system: 20 cases
• War, intelligence and what the British state kept secret: Suez, Bloody Sunday, Iraq WMD and other cases where the British state kept secrets or its official account changed.
• War, intelligence and what the British state kept secret: 19 cases
• British laws that were defended, then abandoned: Laws Britain once defended and later abandoned: the death penalty, Section 28, blasphemy, ID cards and more.
• British laws that were defended, then abandoned: 20 cases
• Everyday British life: things once permitted, then considered unacceptable: Smoking indoors, seat belts, drink-driving, cladding and other parts of everyday life the rules later changed.
• Everyday British life: things once permitted, then considered unacceptable: 19 cases
• Government promises, financial policies and public failures: The poll tax, Black Wednesday, tuition fees, Windrush, the exam algorithm and other government reversals and failures.
• Government promises, financial policies and public failures: 20 cases

Where to start

These cases most clearly show an official account that was later changed or overturned.

Story	Why it matters
BSE and British beef	Public reassurance followed by a major change in the scientific risk assessment
Thalidomide	A drug presented as remarkably safe caused devastating birth defects
Infected blood	A public inquiry found decades of institutional failure and concealment
Post Office Horizon	People prosecuted over a computer system later shown to have serious faults
Hillsborough	The official explanation was challenged and ultimately discredited
Bloody Sunday	A major new public inquiry contradicted central elements of an earlier official account
Iraq WMD	Strong government claims not substantiated by subsequent investigations
Windrush	Lawful residents treated as if they had no right to be in Britain
Opren and Vioxx	Approved medicines withdrawn after serious health risks emerged
Grenfell	Regulatory safety arrangements failed to protect residents
Gosport	Patients were harmed while serious concerns went inadequately addressed
2020 exam algorithm	A system defended as fair was abandoned after its results became public

What the labels mean

• Cover-up: documented concealment or misleading conduct
• U-turn: an identifiable policy or decision was reversed
• Safety reversal: a formerly accepted product or treatment was restricted or withdrawn
• Changed evidence: scientific or medical understanding developed substantially
• Institutional failure: an inquiry or review found serious failings
• Wrongful conviction: a conviction was quashed

Entries that overlap with our fact-checked cases link to the full evidence.

Last reviewed: 12 November 2026.