The Occupy movement really brought some of the issues with POPS into sharp relief. Take this piece by Jill Colvin for DNAinfo. She points out that the legal murkiness that surrounds Zuccotti Park, the epicenter of the Occupy movement, including whether police had the authority to kick out protesters. Whether protesters intentionally occupied that park based on its legal limbo is unclear, but it ended up being a savvy choice.
I should point out that one legal loophole often means there are others, ones that may not work in your favor.