In a recent comment on Shoefiti.com, a police officer named Jim Wheeler shared his thoughts on the meaning of shoes hanging from powerlines:
Being a Police Officer for over 20 yrs. and 18 as a K-9 Handler, narcotics interdiction officer for the last 8. I can attest to the tennis shoe theory.I can of course only speak for my area, however it is one of the ways the gangs and dealers mark their territory. Most often the area marked could possibly see an increase in home burglaries and thefts in general. Keeping eyes and ears open and being able to be a good witness is a good deterrent.