| This might be|
|But we're not sure|
Singh was sued by the British Chiropractic Association (BCA) following allegations of libel due to his (correct) characterization of Chiropractic woo as "bogus". The offending article was removed from The Guardian pending the result of the legal process, but is now available again. It's possible that the litigation raised the profile of the more crank positions of chiropractic medicine well above what people previously thought.
In a more recent turn, the BCA published (and quickly retracted) an allegation that Singh was motivated by malice - a defamatory statement that opens up the possibility for Singh to counter sue the ass off the BCA (we at Rational Wiki aren't saying he should follow such childish litigation, but we won't lose sleep if he does). This was summed up quite nicely in the Science, Reason and Critical Thinking blog.