Ask any dog owner and they'll tell you that dogs can feel guilty, but what does science say? Julie Hecht of Eotvos Lorand University in Budapest did the experiment to find out:
Given that so many dog owners report that they believe that dogs who have broken a rule act guilty even before the dog’s transgression is discovered, and given that owners report that they are likely to scold their dogs less following the display of guilty behaviors, it stands to reason that dogs’ “guilty look” may just be a learned response. If scolded, a guilty look might simply serve to reduce the duration of the negative social interaction.
Keeping this in mind, the researchers designed an experiment to answer two questions. First, would dogs who had misbehaved in their owners’ absences behave differently when greeting their owners than dogs who had not misbehaved?
Second, would owners be able to determine, upon entering a room and relying solely on dog greeting behavior, whether or not their dogs had actually transgressed?
Jason G. Goldman of Scientific American's The Thoughtful Animal blog has the results: Link