I used to work for a guy who was famous around the office for his double-negatives - "I don't disagree with you" was almost his tagline. Thanks to my good friend Matt, we've finally identified one better than our old boss... From the San Antonio Express News article http://www.mysanantonio.com/news/traffic/stories/MYSA080307.1A.local.bridge.34310f6.html:
"A deficient bridge has structural damage or isn't as strong as it should be. It isn't not necessarily unsafe but could be, and officials often need to restrict traffic and weight loads." (emphasis added)
A "triple" negative? I wonder how long it took them to come up with that one...
[Ed: by the time I got around to posting on this, the Express News had gone in and cleaned up the article. Still, it was worth posting anyway as it was such a work of art...]