Google; Helping Hackers

       Today, I read an editorial by Bruce Schneier about how Google ended up helping Chinese hackers in a "politically motivated attempt" to find information. In order to help law enforcement personel, google created a "back door" acess system to Gmail. This system was created in order to help governments catch criminals, but it was just used by criminals to research governments. While i'm not exactly sure what happened, one thing is clear; something entended to keep us safe has made the internet a lot more dangerous.
      Like the article suggests, this is similar to the NSA's phone wiretapping. Here's where my question to you comes in; at what point are these information-getting and security invading practices crossing the line? At what point do these safety procedures become unsafe?
     If you were a society to make a law regarding when the invasion of privacy is okay, how would you write it? Would you say it is okay when there is a warrant? Is it okay whenever as long as the invasion is by the government? Or would you say invasion of privacy is never okay under any circumstances? Is there an option i'm missing? 
      How and at what points should companies assist a government's invasion of privacy?
      I tend to think that "back-door" access are unsafe. Whether it's wiretapping or entrance into someone else's email, companies should not make special systems because they could be hacked or abused. However, if there's a dangerous criminal on the loose, and his email hints his location, I can't say i'd be opposed to looking at it. It's a fine line, and I don't know where I stand. How do you feel?