Mental Deficiency Act 1913

Mental Deficiency Act 1913
Act of Parliament
Long titleAn Act to make further and better provision for the care of Feeble-minded and other Mentally Defective Persons and to amend the Lunacy Acts.
Citation3 & 4 Geo. 5. c. 28
Territorial extent England and Wales
Dates
Royal assent15 August 1913
Commencement1 April 1914, except 1 November 1913 as respects the constitution of the Board of Control, and the appointment of the secretary, officers, and servants of the Board
Repealed1 November 1960
Other legislation
Repealed byMental Health Act 1959
Status: Repealed
Text of statute as originally enacted

The Mental Deficiency Act 1913 (3 & 4 Geo. 5. c. 28) was an act of the Parliament of the United Kingdom creating provisions for the institutional treatment of people deemed to be "feeble-minded" and "moral defectives". People deemed "mentally defective" under this Act could be locked up indefinitely in a "mental deficiency colony", despite not being diagnosed with any mental illness or disability, or committing any crime.

In the late 1940s, the National Council for Civil Liberties discovered that 50,000 people were locked up under the act, and that 30% of them had been locked up for 10-20 years already. The act remained in effect until it was repealed by the Mental Health Act 1959, but people detained under this Act were still being discovered in institutions as late as the 1990s.