Emergency Powers (Defence) Act 1939

The Emergency Powers (Defence) Act 1939 was emergency legislation passed (August 24, 1939) just prior to the outbreak of World War II by the Parliament of the United Kingdom to enable the British Government to take up emergency powers to prosecute the war effectively. It contained clauses giving the government wide powers to create Defence Regulations which regulated almost every aspect of everyday life in the country. Two offences under the regulations were punishable with death.
https://en.wikipedia.org/wiki/Emergency_Powers_(Defence)_Act_1939
http://hansard.millbanksystems.com/sittings/1939/aug/24
http://ww2talk.com/index.php?threads/defence-regulations-emergency-powers-defence-act.19087/

Death penalty

Originally the regulations did not create any capital offences, since the law of treason was thought to be sufficient. Defence Regulation 2A provided that "If, with intent to assist the enemy, any person does any act which is likely to assist the enemy or to prejudice the public safety, the defence of the realm or the efficient prosecution of the war, he shall be liable to penal servitude for life."

However, in 1940 amendments to the regulations created two capital offences: "forcing safeguards" (breaking through roadblocks etc.) under regulation 1B, and looting under regulation 38A. A third new capital offence, called treachery, was created soon afterwards by the Treachery Act 1940.
https://en.wikipedia.org/wiki/Defence_Regulations

The Treachery Act 1940 (3 & 4 Geo. VI c. 40) was an Act of the Parliament of the United Kingdom enacted during World War II to facilitate the prosecution and execution of enemy spies, and suspended after the war and later repealed. The law was passed in the month after Nazi Germany invaded France and Winston Churchill became prime minister (23 May 1940).
https://en.wikipedia.org/wiki/Treachery_Act_1940 .

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