The Case of the Missing Diamond Ring

I heard an interesting story recently. A woman at a dinner party said that her mother (let’s call her Jane) was having lunch at a well-known and expensive New York restaurant when she went to the ladies’ room. While washing her hands, she made the cardinal sin of removing her diamond ring, and then forgot to retrieve it before she left.

Jane realized what she had done and, according to her estimate, returned to the ladies’ room within 10 minutes. But the ring was gone. It had about 5-1/2 carats of diamonds, emerald cut and channel-set all the way around the ring in yellow gold. She immediately reported the loss to the restaurant’s owner, but the ring had not been reported found by any of the restaurant’s staff, including the ladies’ washroom attendant. Jane had noted that the attendant was not in the ladies’ room when Jane washed her hands, but that she seemed to have visited in the intervening 10 minutes, since the towels had been refreshed (and the tip plate emptied) since Jane’s first visit to the ladies’ room. But the restaurant owner assured Jane that the washroom attendant was an employee of good and long standing, and could not have taken the ring. After hanging around a while longer and leaving behind a note begging for the ring’s return, Jane finally left the restaurant empty-fingered.

When she went to file a police report, the detective made an interesting remark. As far as his experience was concerned, he said, Jane would have been more likely to have the ring returned at a McDonalds than at the very swanky restaurant where it had been lost.

I would love to know if that is true. There are a lot of variables to consider, among them:

1. The quantity and characteristics of the other patrons.

2. The quantity and characteristics of the employees.

3. The volume of traffic in the ladies’ room.

4. The presence of surveillance cameras.

Etc., etc., etc. This strikes me as a potentially interesting experiment to run (a job for the MythBusters, maybe?) — planting a ring in a few McDonalds’ as well as in a few upscale restaurants, then comparing what happens. I’m guessing the hardest part would be to get a video camera allowed in the bathrooms. And I guess you might want to use a fake ring (which, of course, might well alter the outcome of the experiment).

What do you think would happen?

At the very least, we’d also learn what kind of people are most likely to wash their hands after using the bathroom.


Thank you #11. Didn't care for his response/logic either


Interesting poser. My first thought was that the person who found the ring felt the owner could afford to lose it (had other pieces and/or insurance). Or there is the chestnut about the inherent honesty of poor versus rich. I would like to see this experiment done. Where are grad students when you need them?


I guess the reasoning of a lost 5-1/2 carats ring at a McDonald has a better chance of being returned is that people will think the ring is very likely a fake and thus not worth keeping. Who has that much money would use a McDonald washroom?


This situation reminds me of the bagels sold on the honor system that you mentioned in your book. If I recall correctly you also mentioned that CEO's were more likely to not pay for the bagels as compared to lower level employees.

Mike B.

Individuals eating at McDonalds are less likely to be economically successful -- lack of economic success strongly correlates with lower intelligence -- lower intelligence strongly correlates with religious belief -- only someone who believes in hell (or is stupid) would return a 5 1/2 carat ring?

Is that the logic? Because the argument that "rich folks" are less ethical than "poor folks" induces an almost automatic eye-rolling reflex.


Well, McDonald's bathroom's are probably busier, so there's more of a feeling that there could be witnesses.

Also, people at McDonalds are more likely to have young children with them. If a child finds a ring, he or she would probably tell a parent, who would be likely to have to teach the child what we do when we find objects of value (try to return them). Likewise, if a parent found the ring in the presence of the child, they would feel more obligated to set an example of social responsibility.


Read Anthony Bourdain's "Kitchen Confidential". Given his description of the type of people who staff restaurants -- even (especially?) swanky ones -- this should be no surprise.


A fast food chain like McDonalds could certainly expect a much higher volume of customers than a more upscale and expensive lunch joint. However, each patron would probably have incentive to stay away from the McDonalds restrooms, resulting in an overall decreased volume of traffic. Also, I have yet to see a McDonalds with a dedicated washroom attendant, certainly not one that stops in every ten minutes. Assuming a restaurant like McDonalds has a higher employee turnover rate, it also has incentive to keep closer tabs on its individual employees. Finally, whoever took the ring most likely recognized that a patron of an upscale restaurant could likely more than afford to replace such a ring, and thus felt fewer moral qualms before purloining the ring in question.


I am not 100% sure whether outcome of such experiment will match detective's assertion or not. However if it does then following two factors may play some role : 1) McDonald's employees may not be able to 'guess' price of the diamond ring as accurately as expensive restaurant's employees. To be precise, how much expensive is this ring ? 2) McDonald's employees may have higher probability of prior run-ins with laws (I do not know if there are statistics to prove this) and they know they are usually suspected in such events.


I live in France and have two France-related comments to make. First, there is a pervasive "finders-keepers" rule here. I've never lost anything of value, but have twice lost a junky toy/stuffed animal due to my baby/toddler throwing it out of the stroller in a supermarket. As soon as I realized the toy was gone, I did everything I could to retrieve it for my child, including retracing my steps, asking many people, suspiciously eyeing other shoppers with children, and having an announcement go out over the store intercom. My (French) husband says that when you find something here, it's yours. Second, I've noticed in public restrooms that few people wash their hands. I was pretty surprised even to see a grandmother-type whisk her grandchild out of the bathroom without washing.


I don't buy the "rich people are less ethical" argument, but this story certainly seems like strong evidence that economic success is not strongly correlated to intelligence. Or, at least not the intelligence of trophy wives.


Mike B. - you think the argument that rich folks are less ethical than poor folks is eye-rolling, while you propose that poor folks are less intelligent than rich folks is a reasonable supposition ?

Level of education is correlated with wealth - NOT intelligence, and I know plenty of post-grad 'achievers' (maybe you are one ?) who provide ample evidence for this distinction.


Assuming the guy's comment is true, which we don't know--

Maybe people who lose things at McDonald's just assume it is gone, with no hope of return, and don't file police reports. They'd be more outraged at the thought of a theft at a "nice" place and more likely to report it.


I chip in as i have experimented a similar case with different variables (which is what economists should dream of)

I lost my cell phone in a movie theater in Manila, Philippines (yes, it was in my trousers pocket, silly)
It was found by the cleaning employee and brought back to the "security officer" . Considering that it was a brand new 150 Euros ( so low value compared to the ring) cellphone, worth approximatively 2 months of salary of that person, I was quite surprised when told that they had found my phone.

I am french, and i am quite sure that i would not have found it again in the same conditions in France.

Ah, by the way, french don't wash hands because toilets in cafés in France are awful & dirty (which is quite a strong incentive to wash hands, but entails the opposite) I personally go into Mc Donalds (or starbucks) to have a fair standard in toilets.


Ugh, I am so surprised whenever I'm in a public bathroom and see people leave the stall without washing their hands. Part of me wants to yell out, but then I avoid such confrontations, because I would feel rude. I should yell though -- because their germ-spreading is much more rude than me calling them on it.


I doubt that there is a significant link between honesty and wealth. So given my assertion, I think there is an equal chance of a dishonest person discovering the ring at McDonalds or the expensive New York restaurant.

Now what is the chance that the dishonest person will attempt to keep the ring? I think his decision will depend mainly on three factors: the value that the person places on the ring relative to his own overall wealth, the likelihood that he can successfully leave the restaurant with the ring, and the anticipated ease with which he can trade the ring for cash (or obtain value in some other way).

I think that the finder of a ring found in the expensive New York restaurant will be more likely to anticipate that it is highly valuable than if he finds the same ring in McDonalds. I also think that the finder at the expensive New York restaurant is more likely to believe that he is highly intelligent (compared to the average dishonest finder at McDonalds) and therefore is more likely to believe that he will be able to successfully take the ring and trade it for cash.

Therefore, I think the chance of a returned ring is better at McDonalds.

Also, this story sounds incredibly unlikely to me. Would anyone really take off an expensive ring in a restaurant washroom and leave it behind?


Michelle Wetzler

I am one of those people who loses things constantly and I must say that I find that people are incredibly honest. I have left behind: my watch, diamond rings, purses, wallets, phones, jackets, etc. In each case I returned to the scene where I left the item (movie theater, store, restaurant, cafe, bar, etc) and found that some kind patron or employee had carefully tucked it away at the front counter, waiting for me to come and reclaim it. Most of my life I have lived in the small-town midwest (stereotypically kind), but I have noticed the pattern here in Hollywood as well.

I admit my whole story is anecdotal, but maybe one of the factors is that my stuff definitely does not look like it belongs to a rich person. My story might be different if I were leaving behind designer items.

Pedro H. Carvalho

I live in Brazil. Once I lost my wallet with 600 reais (more or less 400 dolars) in the bus here. The not-realy-wealthy lady who cleans the bus found it and gave me back - every cent. Does this information help? ;)


I recently lost a 2 months old (new) MacBook Pro at a Tim Hortons restaurant in Montreal. I just left it in my bag, hanging at my chair. I called them when I found I had lost it but it was nowhere to be seen. However it was found three hours later and returned to me. All intact.

I don't know Tim Hortons being a cheap restaurant chain helped in the returning or that people are just very honest in Canada.

(Three weeks later I forgot another laptop in a first class train and that was also returned to me.)


In cases like this, I tend to wonder if the patron who left the ring maybe didn't accidentally lose it somewhere else and wanted a convenient excuse.