Why didn't Sergeant just park outside the guys house and wait

Besides the fact that it wouldve been a very short movie, I don't understand why he waited til the Purge began and then tried to drive to the guy who killed his sons house. Wouldve made alot more sense to just drive over hours before, park outside his house, and wait for the Purge to commence then walk into his house and murder him. That way he isnt trying to drive across town while murderous lunatics are running around.

Dear Warden, You were right. Salvation lies within.