Add the Federal Communications Commission to the list of legal headaches for Google caused by its Wi-Fi spying debacle.

The Wall Street Journal reported today that the FCC opened an investigation into the Google Street View scandal earlier this year, but hadn't disclosed it until recently. As is common knowledge by now, Google disclosed in May that Wi-Fi sniffing equipment on its Google Street View cars--which the company says were intended to capture only benign data--also captured so-called "payload data," including e-mails and passwords.

It's not clear exactly what the FCC could be looking at, but if Google were determined to have intentionally captured the data it could be in violation of wiretapping laws. The company has insisted the collection was inadvertent, and the FTC recently ended a separate inquiry into the matter without any penalties.

Google is still facing a class-action lawsuit over the practice that might ultimately uncover the most information about its Wi-Fi Street View program.