you got robbed by imperial troops?
I remember one time north west of Solitude I ran into these 3 "Imperial Soldiers" who demanded I pay a toll to continue down the road. Next to these 3 dudes were 3 looted bodies so I assumed that these were mere bandits posing as the imperial troops they killed.
If you're with the Stormcloaks by then, that little event has a cool extra dialogue option, something along the lines of this:
"Only three legionaries against one Stormcloak? Hardly seems fair"
What made it more awesome was being clad in the Stormcloak Officer Uniform.