Here are three conspiracy theories that turned out to be true.

1. The UK’s secret human experiments at Porton Down

The Claim: For decades, allegations persisted that the UK government conducted unethical tests on military personnel and civilians, exposing them to nerve agents, LSD, and biological weapons without informed consent.

The evidence:

Declassified documents and a 2006 National Archives release confirmed that between 1945 and 1989, over 20,000 British servicemen were subjected to tests involving sarin, VX, mustard gas, LSD, and anthrax simulants (Porton Down Volunteer Programme).

In 1953, Leading Aircraftman Ronald Maddison died after sarin was applied to his arm during a Porton Down experiment. The UK government denied responsibility for 50 years, but a 1999 inquest ruled his death an “unlawful killing“. Maddison’s father was allowed to attend the inquest into his son’s death, but under a severe warning: he would face prosecution under the Official Secrets Act if he disclosed any details of the circumstances, even to his own family.

A 2008 compensation scheme acknowledged harm to test subjects, though the full extent of the program remains disputed. Investigative journalists like Rob Evans (The Guardian) and veterans such as Eric Gow and Gordon Bell (who suffered lifelong health effects) helped uncover what had happened. 

The Ministry of Defence ensured secrecy by delivering Maddison’s body in a bolted-down steel coffin. Without his family’s knowledge or consent, numerous body parts,including the brain, spinal cord, skin, muscle, stomach, lung, and gut tissues were retained and used for years in other toxicology experiments.

The conclusion: While once dismissed as conspiracy, the Porton Down experiments are now a matter of public record, with official inquiries confirming unethical testing on participants.

2. GCHQ’s Tempora Program: Mass surveillance revealed

The Claim: In the early 2010s, privacy advocates warned that UK intelligence agencies were collecting vast amounts of digital data, including emails, phone calls, and internet activity, in a secret dragnet operation.

The evidence:

Edward Snowden’s 2013 leaks (published by The Guardian) proved that GCHQ’s Tempora program was intercepting data from undersea internet cables, storing communications, and sharing information with the NSA.

The program captured phone calls, emails, browsing history, and metadata without individualized warrants. In 2016, the Investigatory Powers Act (colloquially known as Snooper’s Charter) legalized many of these surveillance practices.

The conclusion: What was once dismissed as paranoia was confirmed by Snowden’s leaks: that the UK government was conducting mass surveillance on an unprecedented scale.

3. Undercover Police: Fake identities and deceptive relationships

The Claim: For years, activists alleged that British police officers were living under deep cover, adopting false identities for years, even forming relationships and having children, while spying on political and activist groups.

The evidence:

A 2015 public inquiry revealed that at least 10 undercover officers had long-term fake identities. Some even maintained families who were unaware of their true roles. Bob Lambert, an officer who infiltrated activist groups, fathered a child under his fake identity before disappearing. This left lasting psychological trauma. The ITV documentary The Undercover Police Scandal: Love and Lies Exposed (2025) detailed how women unknowingly entered long-term relationships with undercover officers, only to later discover their partners were married police spies.

The conclusion: While it sounds like something out of a spy thriller, the undercover policing scandal has been officially acknowledged, with inquiries confirming that officers deceived partners for years as part of their operations.

The Conclusion

These true conspiracy theories may be an intense read.