Most, if not all ISPs do some form of Deep Packet Inspection under the guise of maintaining QOS, security mitigation, legal compliance, and/or national security. Some have even gone as far as offering customers the ability to "opt out" for a fee. See this article.
While some tech savy customers can circumvent DPI by using a VPN. Most customers will stick to using HTTPS which is "supposed" to create an encrypted tunnel from the client to the intended website's server. But it is possible for ISP's to forge the certificates in order to facilitate DPI or eavesdropping.
By running DPI on customers connections, are ISPs violating privacy laws? What recourse does a customer have against this type of violation?