When you stuff the base of a toilet with tissue paper to avoid an embarrasing splash and also to avoid taking the blame for the rancid smells as you leave. This is usually accompanied by very careful, stealthily release of ones flatulance. For added effect you can also shoot a disaproving look towards an engaged cubicle as you wash your hands (making sure fellow hand-washers see) to shift the blame onto an unsuspecting victim. This especially applies in a public bathroom and is typically actioned by women.
The bathroom in the shopping centre was packed, so to keep her dignity, Sarah let rip with a PARACHUTE POO, thus leaving everyone oblivious to the fact that it was her that just cut the cheese.