His name is Colin Greenwood and he has compared the crime rates in England from the Victorian era with those in modern England. I don't recall the exact figures but there was something like three or four armed robberies per year during the late 19th and early 20th centuries.
During this period, Great Britain had some of the most liberal gun laws in the world, even more permissive than in much of the U.S.
"At first glance, it may seem odd or even perverse to suggest that statutory controls on the private ownership of firearms are irrelevant to the problem of armed crime, yet that is precisely what the evidence shows. Armed crime and violent crime generally are products of ethnic and social factors unrelated to the availability of a particular type of weapon. The number of firearms required to satisfy the 'crime' market is minute, and these are supplied no matter what controls are instituted. Controls have had serious effects on legitimate users of firearms, but there is no case, either in the history of this country or in the experience of other countries in which controls can be shown to have restricted the flow of weapons to criminals or in any way reduced crime." (Chief Inspector Colin Greenwood, West Yorkshire Constabulary, Police Review, 10 Nov 78, P1668.)
On the author's last trip to England, he found that a legal .45 Colt handgun could be purchased for 500 pounds, and an illegal one for fifty. Purchasing the legal firearm required a police check of the applicant's reputation with his employers, his neighbors, and his relatives; purchasing the illegal one required 50 pounds and fifteen minutes of enquiry of shady characters in a Soho bar. It is evident that their registration system is a failure as a method of firearms control, despite the major control advantages of being situated on an island.
source: http://teapot.usask.ca/cdn-firearms/NFA/firectl.bas
There is a large amount of excellent evidence Greenwood enters into the record - most of which was obviously ignored by Parliament when they did their last gun ban. Here is a sample (Early Legislation, point 5)...
5. The evidence shows that, despite the existence of an absolute right to keep arms and the very widespread ownership of firearms as evidenced by the state of the gun trade at the time, the use of firearms in crime and disorder was extremely rare.
Greenwood goes on to quote some statistics. This Appendices is well worth the reading and gives an excellent overview of weapons laws in Great Britain stretching back to the longbow, including some legal basis of our own 2nd Amendment. The overall Parliament Report is here (Report) and here (all Appendices).