### Clue: Friendly pair of criminals shelter a dozen (in separate groups) (9)
### Answer: CONVIVIAL 
 ### Explanation: Definition: Friendly
 [CON, AL](short for "convict", and Capone, American gangster, viz. a pair of criminals) **containing**(shelter) VI,VI(Roman numerals for 6 and 6, which added together give a dozen in 2 separate groups).