I thought NSLs were supposedly non-contestible, broad and were for communication detail. These don't seem to be any if that.
The requests we have received have been from a variety of organizations (but signed by a magistrate) ranging from local law enforcement to three letter acronyms and one entity that is neither. While the requests don't say why the order is being issued, we usually receive a call from the agent/detective beforehand and dialog ensues in which they explain what's going on.
While many companies will just give the info, we scrutinize the request and ask the agent/detective politely and apologetically that we can help, but only if they acquire a court order. We have caught not-legitimate requests before, so we verify the request is legit before responding. We have never been asked for content of communications. If Google is not doing the same thing... oof. Just as a matter of process I assume they do. I recall in the past some networks having right in their WHOIS info, how/where Law Enforcement can send FAX requests.