In NH, you are responsible for all data that passes your wifi point secured or not.
Where is this codified?
NH - This is a Bill that has passed, but not signed into law...
https://www.gencourt.state.nh.us/rsa/html/LXII/638/638-17.htm https://www.gencourt.state.nh.us/legislation/2003/HB0495.html
Use the full text. This bill attempts to clarify/legalize using someone else's wifi when I(a)(1)-(3) are reasonable assumptions... commonly such as when the operator has not 'secured' their wifi... the "it's open, so it must be ok" defense. (Defense to a charge by an annoyed operator, a "look, a user in their car!" charge by the police, or an accessory charge to a greator crime of the defendant.) It tries to make 'know/belief' easy for the lay user to assume by using the word 'secure' and attempting to create some kind of obvious 'security' wall but it doesn't define what that boundary is. What about the day when there is some popular 'click here to go online' tool that does WEP guessing in the background behind a pretty GUI? Your belief may have just changed, and not in a good way. Next, note that 'shall be responsible for securing' does not mandate any given security level... be it open, at any other level, or by any given means. While you could seemingly document your 'security' choice as open, closed, or whatever (to satisfy whatever action this clause is trying to make you do)... the choice itself makes no difference to us because: It doesn't say anything about the operators culpability for what traverses their wifi/node. The context of that clause, and the bill and code as a whole, appears to be regarding users and is of no use or affect regarding operators. Which is what this list cares about and would like to know. That's one interpretation, call a lawyer and make your own.
Other interpretations and background... http://www.wired.com/gadgets/wireless/news/2003/04/58651?currentPage=all
In NY, if your wireless is secured (pw protected) you are ok.
Where is this codified?
Penal Code Section 156.05 Unauthorized use of a computer A person is guilty of unauthorized use of a computer when he knowingly uses or causes to be used a computer or computer service without authorization and the computer utilized is equipped or programmed with any device or coding system, a function of which is to prevent the unauthorized use of said computer or computer system.
Again, this applies to the user. Every state has similar laws. I won't bother to link or pick at this one. Other than to laugh at how the operator's "'equipped' but disabled" choice might make open access a crime. So if you're used to leeching in NH, stay the hell away from NY :)