Caleb Crain summarizes historian Douglas Allen's theory as to why crime changed dramatically after the Industrial Revolution:
Before the nineteenth century, Allen writes, theft was easy to detect. If your transport was a horse, you could recognize it. (For that matter, it could recognize you.) Not only was your coat hand sewn, but a tailor looking at its fabric could probably tell who had woven it. If any of these items were stolen, they were easy to reclaim if they could be found. With the advent of the industrial revolution, handmade goods gave way to standardized commodities, which all look alike, and it ceased to be possible to know an object’s provenance just by looking at it. The phrase "possession is nine-tenths of the law" came into vogue, and it was made illegal to hold stolen goods. After all, once goods became untraceable, they were all too easy to fence.
The Dish 