It seems that electronic surveillance may have played a big role in the government’s evidence. Among the documents filed by the U.S. attorney’s office as part of the proceedings against MegaUpload are reams of internal electronic documents apparently gathered from MegaUpload’s own computers. The material includes internal emails, as well as Skype IM chat logs.

According to internal FBI sources cited by CNET, the government obtained warrants to conduct electronic surveillance of MegaUpload. The surveillance was likely conducted using government-issued spyware, which would have been able to gain access to email data and Skype chat logs stored on MegaUpload’s computers. While Skype only maintains logs of users’ activity going back 30 days, logs can be kept on users’ hard drives indefinitely.

Some of the material intercepted by the FBI appears pretty damaging to MegaUpload founder Kim DotCom. One conversation from 2007 is particularly damning. According to the records obtained by Stuff’s New Zealand office, the head programmer and co-founder at MegaUpload were worried about a MegaUpload’s “risky” situation, and wondered whether DotCom could be trusted not to take the company’s money and run.

DotCom and the other MegaUpload employees who were arrested are currently still in New Zealand. The U.S. government has requested they be extradited to America for trial on charges that MegaUpload knowingly facilitated copyright infringement.