Something I consider but most articles do not: jurisdiction. I want and use a VPN in Sweden for a reason. I wouldn't go anywhere near any VPN with even a tiny US footprint. Similarly, I wouldn't use a VPN in my home country. Location location location.
No written laws specific to that point. But just look at the NSLs Yahoo released a couple days ago. They can do whatever they want whenever they want. While such things may be possible in Sweden, if they do happen they are extremely rare. The US is the surveillance state.