Sorry but I have to interject my thoughts here...
As I am an employee of government information services I must comment!! It is your responsibility to assist the organizations in Chicago to close any loose holes in network that you gained access to. If you choose not to disclose your findings then you are not a "ethical" hacker but rather guilty of criminal trespass and should you find access to a Chicago law enforcement data network, I doubt seriously that you will not be given the courtesy of a "thank you" but rather the gift of a criminal record.
Anyone that would gain unauthorized access to any of the networks that I am responsible for, there wouldn't be any issue of "golly gee, thanks for pointing that out!!" as ANY such activity as you describe in this day and age is something that is not taken lightly.
While I am no were near Chicago and have nothing what so ever to do with the network security of such in that area, if you were to do what I believe you are doing in the Chicago area in my area, I would conduct an investigation against you and your activities; including turning over my findings to law enforcement for criminal charges.
An act of accidently gaining access to a data network system which is considered to be a closed private network would be understandable, but not reporting and then pursuing additional unauthorized access would in violation of local and federal laws regardless of what your intentions are. This is not a grey area for you to decide on your own, you are risking a lot more perhaps that you understand.