Technology makes a difference here. For example, it is not illegal to follow someone on a public street. But attaching a GPS device to their car is going over t

Technology makes a difference here. For example, it is not illegal to follow someone on a public street. But attaching a GPS device to their car is going over the line, even though the concept is the same. The difference is the lack of physical limitations. You no longer have to follow one car for a short time from another, you can follow hundreds of cars for long periods from your living room. Similarly, if someone is speaking out loud in public, you can listen, but wiretapping is still wrong. And just because someone can view your actions in public doesn't make it okay to monitor and log every person on every square foot of public space continuously.