Yeah, it was highly flawed from the beginning. The guards were given no training, had little to no supervision, had virtually no set rules and procedures they were to follow, instead basically making things up as they went along, and thus were not accountable for their behavior.
In short, the situation couldn't have been a better setup to encourage bullying and abuse.
If anyone's interested, theres a German movie very loosely based on this experiment,
The Experiment.
Gilda