My friend recently switched his ISP to Charter. Shortly after, he got an email.

It was a cease and desist letter. Would it be safe for him to continue downloading, if only through private trackers and direct download links?

This question shows up relatively frequently. Here are two threads that may help.

http://filesharingtalk.com/threads/4...seeks-guidance
http://filesharingtalk.com/threads/4...ngement-Notice

Charter provides free USENET (Highwinds backend) service - one of the rare few USA internet providers that still includes usenet!

Your friend needs to take advantage of this. That's one safe way of downloading while avoiding any more nastygrams.