### Clue: In court, argue against jail in speech (10)
### Answer: QUADRANGLE 
 ### Explanation: Definition: court
QUAD (slang for a jail, I think, though I can't see it in Chambers) + homophone of "wrangle" (argue) *Thanks to WordPlodder for pointing out that "quod" is slang for a prison, so both it's a homophone of both elements.