This is one of those types of questions where you have to ask yourself:
1) are you wanting the technical answer? Or
2) are you wanting the realistic answer ?
There were some cities in CA hard-hit by the housing value decline on the early 2000's. In some cities, in certain neighborhoods which had been way over-priced at the height-of-the-market, it was not unusual to see several vacant homes PER BLOCK ! Yup, people who just "walked away" from upside down home mortgages.
I knew some guys who took the liberty to go yard-to-yard in such areas, since the abandoned vacant ones were easy to spot. Eg.: un-mowed yard, boarded up or no-curtain-windows, etc... And these guys had no problems. But is that to say they were technically in-the-right? No, of course not. Rather: they were using the "does anyone REALLY care ?" test of reality.