We have a constitution in the Methodist Church which is (mostly) fairly reasonable, and which could often be used to our advantage. Trouble is, hardly anyone knows what's in it; it's just a big book which is toted around the place by ministers, and which most of them don't bother to read themselves. Fortunately, it's not hard to get hold of these days. The 2009 version of CPD (it doesn't change much from year to year, and if someone wants to claim it's changed, make them prove it by producing the updated text) can be downloaded from the Methodist Church website.
Vol 1 (Historic Documents) http://www.methodist.org.uk/downloads/CPD-volume-1-0709.pdf .
Vol 2 (The bit that matters, with all the rules) http://www.methodist.org.uk/downloads/CPD-volume-2-2009.pdf .