Flailing Fecal Matter
Serving a sentence in prison is not a good time, but helping to keep a prison running is a thankless job as well. Not only will many inmates be hostile toward you, but they may also find some purely disgusting ways to show that hostility.
This story is the perfect example of that. Apparently, some inmates have a standard way of expressing their displeasure at the fact that they are stuck in prison. One of the surest ways to make that feeling known is to avoid flushing waste down the toilet and showering the correctional officers with it instead.