2009 UKHL 18

The case **2009 UKHL 18** involved a legal dispute about whether someone, in jail, could be detained alone ("segregated") for safety reasons without it breaching their human rights. The House of Lords (the UK's highest court) ruled that indefinite segregation must balance security needs with the individual's rights. Authorities cannot keep a detainee segregated for a long time without proper review, and such measures should be necessary and proportionate. This decision emphasized that even in detention, people's rights are protected, and authorities must justify segregation carefully to avoid violating human rights laws.