Guard

All but the smallest settlements maintain guards. Soldiers take care of threats from without, guards deal with threats from within. Most of these threats are minor such as drunk and disorderly tavern patrons and minor theft. Still, without the vigilance of the guard there would be lawlessness.  
In Murgulmuir most of the Guard are corrupt and/or incompetent. A character with this background has probably ended theur service or was asked to leave.  
   
Skill Proficiencies: Perception and Insight or Intimidation

Equipment

Longsword or Pike, Chain Shirt or Ring Mail, Shield or Dagger. Hooded lantern, 3 vials of lantern oil, signal horn, whetstone. Pouch with 5gd.

Feature: Night Shift   

Normally a character must sleep for 8 hours with a break of up to an hour to qualify as a long rest.
Guards only need to sleep 6 hours and can break for up to 2 hours during this time.

Feature: Stranger Danger   

If a guard lives in a settlement or has spent at least 3 days either working there or familiarizing themselves with it they are allowed to make a DC 15 Perception roll to spot someone who seems out of place. 

Characteristics

Guards must carry themselves with enough of an air of authority that they can prevent most problems before they get serious. Competent guards seldom have to actually draw their weapons.