at liberty adv. or 
adj. phr. Free to go somewhere or do something; not shut in or stopped. 
 The police promised to set the man at liberty if he told the names of the other robbers.
 The police promised to set the man at liberty if he told the names of the other robbers.  I am sorry, but I am not at liberty to come to your party. Compare:
 I am sorry, but I am not at liberty to come to your party. Compare: AT LARGE
1. 
 [TahlilGaran] English Idioms Dictionary ▲