AOG/Jim
I consider Iain Duncan Smith a despicable person. This is largely because of the disgraceful retroactive law he rushed through a while ago in order to stop his department from compensating people who they had (illegally) been penalizing for not working for free.
Basically he introduced a policy that was a terrible idea from the start, listened to absolutely nobody, and then backed out of the consequences like a miserable little coward using an extremely dubious form of legislation.
http://www.theguardian.com/society/2013/mar/15/dwp-law-change-jobseekers-poundland
http://www.politics.co.uk/news/2013/03/19/ids-emergency-jobseeker-law-sparks-civil-liberties-outrage
He is also remarkably dishonest and was caught out by the Stats agency for making statistical claims that were simply not true (the following link will open a PDF - it is two letters to IDS and the TUC from the UK Statistics Agency. If you don't want to open a PDF, it's covered in my other link below):
http://www.statisticsauthority.gov.uk/reports---correspondence/correspondence/letter-from-andrew-dilnot-to-rt-hon-iain-duncan-smith-mp-090513.pdf
And this was only after a long stream of dishonesty with figures - which IDS is remarkably incompetent at, yet has some kind of toxic aversion to telling the truth - see here for more examples:
http://www.economist.com/blogs/blighty/2013/04/government-statistics
And even before that there was his outlandish claim to have existed "on the breadline" despite being in an extremely wealthy marriage.
These are the reasons I consider IDS a despicable person.