pardon me if I am repeating myself....but
James D. Wright, sociologist, was hired by the Carter Administration to study guns, crime and violence in America in 1977. Wright and co-author Peter D. Rossi produced a report for the government, and expanded it into the book "Under the Gun", Aldine, 1983.
Later they were chosen to write the report on the US NIJ Felon Survey of 1,874 felons convicted of armed crimes, interviewed in 18 prisons in 10 different states. This too was expanded and published as James D. Wright and Peter Rossi, "Armed and Considered Dangerous", (Aldine 1986, 2nd ed 2008, ISBN-13: 978-0202362427).
A summary was linked in a post above at
http://rkba.org/research/wright/armed-criminal.summary.html
Any one have any data more current that 27 yrs old?
Well, there was a 2nd edition of the study in 2008.
Wright and Rossi found felons "obtain guns in hard-to-regulate ways from hard-to-regulate sources".
(No surptise to me. I grew up in a county that was "dry" til 1968 and I know prohibition does not work whether alcohol or guns. From knowing both cops and crooks as friends, relatives, neighbors, schoolmates, I had practical experience that the hoods in my neighborhood in the 1960s were getting their guns from other-than-legal sources.)
Wriight and Rossi found that handgun-using felons expected to be able to get handguns from "unregulated channels" within a week of release from prison*: friends (mostly fellow criminals), from "the street" (used guns from strangers), from fences or the blackmarket or drug dealers (who often run guns along with drugs).
Of gun using felons,
50% expected to unlawfully purchase a gun through "unregulated channels" above;
25% expected to be able to borrow a gun from a fellow criminal,
12% expected to steal a gun.
7% cited licensed gun dealers and 6% cited pawnshops (usually through a surrogate buyer: friend, relative or lover).
40% of the felons surveyed reported stealing firearms, mostly for trade or resale. Sources stolen from included:
37% from stores,
15% from police,
16% from truck shipments,
8% from manufacturers,
21% from individuals.
A few years back, two officers interviewed in Knoxville about a proposed gun law told the newspaper that one in five of criminals they encountered owned a gun, and of the criminals who owned guns 80% got them from illegal sources, so I suspect things have not changed much since the 1980s of the Wright & Rossi study or my experience in the 1960s.
(yeah, I am not a citable, notable or reliable source by academic standards, but Wright and Rossi, professed liberal academics turned gun control skeptics, are.)
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*Surprise, surprise, surpise. A UK study after the infamous 1997 handgun ban revealed that UK gun using felons interviewed in prison expected to be able to get guns within a week or two of release if they wanted one, up to and including submamchine guns. Gun sources: from smugglers, drug dealers, underground "armourers" who specialized in fencing guns stolen, converted blank guns, military surplus smuggled in, and the drug-smuggler/gun-runner overlap was also mentioned as a UK source of guns.
Home Office Research Study 298,
Gun crime: the market in and use of
illegal firearms, December 2006, details the "emerging criminal gun culture" in Great Britain.