You're totally right, that was the wrong link, and the example I found is actually 3 weeks which is so much more reasonable for a serious crime like sending your child to the local school.

http://news.bbc.co.uk/1/hi/england/dorset/8343865.stm

There are others and Wikipedia even has a special section on oppressive use : http://en.wikipedia.org/wiki/Regulation_of_Investigatory_Pow...

[edit: to correct the time frame]