Go for Glaswegians, a violent lot (4)
I believe the answer is:
gang
This clue is a double definition.
'go for glaswegians' is the first definition.
(Scottish term meaning to go)
'a violent lot' is the second definition.
(violent or criminal group)
(Other definitions for gang that I've seen before include "Group of friends, criminals" , "Group (crazy or criminal?)" , "Band of people, usually criminals" , "Organized group of workmen" , "Working group or mob of hoodlums" .)