A Google Webmaster Help thread has one ‘lurker’ reporting that an ex-Googler is using spam tactics to both threaten and intentionally hurt his site. By hurt his site, the ex-Googler is allegedly using hacking and injection techniques to push the site out of the Google search results, thus boosting the ranking for his (the alleged ex-Googler) in the Google search results.

This is a bit hard to believe, but who knows – anything is possible. Let me quote the webmaster from the thread, because he makes it sound like he has been around the block and there is nothing he can do.

It just seems so hard to believe that anyone, let alone, someone who was employed by Google, would go to these measures. Yes, I know, people do take extreme measures, especially in this area, but a former Googler? The thing is, anyone can pretend to be anyone else on the Internet – emails, names and so on, can be spoofed. So this may be someone using a name in order to threaten and scare this webmaster out of the competition. This wouldn’t be the first time Google had impersonators on the webmaster side of the coin.

Hard to know for sure, based on the information I do and do not have.

Forum discussion at Google Webmaster Help.