Green’s Dictionary of Slang

1. (UK prison) subjected to a diet of bread and water.

1925

E. Jervis 25 Years in Six Prisons 20: Bill turned round and ‘sloshed the loafer in the jaw,’ for which he was ‘reported’ and ‘cased’ (which means punished) with three days’ bread and water!

2. (UK Und.) charged with an offence.

1950

P. Tempest Lag’s Lex.