Police service records and Court and Criminal records
Middlesex Criminals Website - 2009 a new Rootsweb discussion list
History by the Yard History by the Yard - http://www.historybytheyard.co.uk/
Police Roll of Honour Trust - http://www.policememorial.org.uk/
Metropolitan Police Records - reference details can be found at http://www.met.police.uk/history/records.htm -
most of these need a visit to TNA(PRO) at Kew The National Archives
Also try The Black Sheep Index which includes a Police Index
The Proceedings of the Old Bailey, 1674-1913 http://www.oldbaileyonline.org/
London Police Divisions and Research http://homepage.ntlworld.com/hitch/gendocs/police.html
British Transport Police <http://www.btp.police.uk/History%20Society/History%20Society%20Main.htm>
Police Orders: The following used to be useful www.policeorders.co.uk which defaults to http://www.externalserver.me.uk:8085/ - as of January 2007 they say under searches " please email searches@policeorders.co.uk. There will be a small charge.". I do not know the charges and I would hope not credit card but something like Paypal. I know nothing about the new owners of the site so this is not a recommendation but the reference kept here as many people knew Police Orders.
For paid research into your police ancestors I would suggest using someone on my Researchers - suggestions for employing someone for UK research
Plus there is a Rootsweb list
http://lists.rootsweb.com/index/other/Occupations/POLICE-UK.html
And this was listed recently re Metropolitan Police Historical Archives http://archiver.rootsweb.com/th/read/police-uk/2006-05/1148298136
Return to UK Military - and Police links