This is a serious warning to all visitors to Paris that during your visit you will no doubt be scanned by pickpockets, whose deft hands will reach into your bag or pockets, determine if you have anything worth stealing, and make their getaway without you having a clue that you've been robbed.
It happens everyday, usually, but not always in crowded places like the metro, or in tourist attractions like museums, where you might think you're safe. The pickpockets range from gypsy kids to well-dressed middle aged, professional men and women.
On our last trip to Paris we experienced no fewer than six incidents (that we noticed) of people reaching into our daypacks and pockets searching for money or valuables. Confronted, one thief dropped the wallet in his hand, to avoid being caught. Another time in the Musee d'Orsay, a well dressed woman was caught with her hand in the pocket, and was brought to security with her hand held firmly in the pocket. We figure they probably just escorted her out of the building.
So no matter where you are, keep your valuables in a money belt, or in an inside jacket pocket. Cameras should probably be kept close, around your neck, in front of you.
Pickpockets are rarely if ever violent, and try to do their deeds unnoticed. But reports of muggings where violence or threats of violence were used are becoming more numerous.
Be careful in certain areas late at night. If you use the metro, you're most at risk. Pickpockets will come up behind you when you're buying a ticket, or going through the turnstile or entering or leaving a train car, or just walking through a passage. We recommend you don't travel alone, and keep your eye on each other and those strangers around you. It's a shame to have to be so paranoid, but if you carry valuables that you don't want to lose, it's essential! If you can, leave your valuables behind, and take just as much as you need. Use traveler's checks and ATM cards for purchases. Credit card information should be kept separate in case you need to report them stolen.
You're supposed to have personal identification with you at all times in France, so most tourists carry their passports. These are very valuable, worth thousands of Euros, and a prime target for pickpockets. Keep these as safe as possible!
The French laisse-faire attitude towards theft and those who commit such acts is probably a result of the more fortunate pitying the less fortunate (think Les Miserables). This has reinforced a subculture where pickpockets thrive on unsuspecting tourists. The general feeling is that if you're stupid enough to let someone steal your valuables then you probably deserve to have them stolen.
Unless you catch the person in the act, and can find a gendarme, or escort them to some security person, there's not much you can do. Several times I saw female tourists crying who had just realized they'd been the victim of a pickpocket. Don't let a pickpocket spoil your trip!