I recently listened to a witness describe a sighting from over 20 years ago that happened at night under little/no artificial lighting. During the telling of the event, the witness had a specific date and time, and many details about how the event unfolded, he further mentioned that the sighting happened under full moon illumination. When I checked the almanac of lunar records for that date and location it reveals that the moon had set hours before the stated time of the event and that the moon was one day past new moon, which means about 1% illumination of the disk. Should I chalk this up to poor memory? After all it was 20+ years ago. But at the same time, there were so many details the person recounted in the story, how could such a mistake about the moon's illumination happen? Or was this a case of partial or full deception to create a better foundation for a tall tale? Just curious about other's opinions if faced with such a hole in a story. I think because of this doubt, I throw it out. But what would you do?

I would recontact the witness to do a second interview. Somewhere in the middle of the interview passingly ask about the date. If he stands firm by the date and the full moon chunk it.

I agree with Bitter Monk, do a second interview and have him clarify where the moon was in relation to his sighting, what the date was, etc. If he sticks to his story about the full moon, file it away as a tall tale.

Usually the amount of intricate detail gives it away---there are few humans on the planet who after many years have perfect and vivid recall of such specifics. Because as humans we like patterns and are confused or frustrated by "holes" in a story, these holes get filled in with things that may or may not have happened.

The term "fish story" exists for a reason!

You might consider that all information is potentially useful. For example, the SRI database has a section for Misidentifications and I think for hoaxes as well. I would think you should make note of the discrepancy but dont nessicarily think you should throw it out. How people misidentify or go about trying to pull a fast one can be educational in their own ways.

Yes, it does sound like a possible red flag to me

It does you're right, however Humans make legitimate mistakes & that's what makes us Human. It's the illegitimate mistakes that you have to wotk out...

True. You can't automatically dismiss everything because of a few possible human errors.

Exactly, yet they do raise Red Flags, like you said..

I agree, and the problem with filling in those holes would be: what's the truth and what's a patched over hole? How do you separate what might be fact from what might be fiction. It makes the whole encounter suspicious. If someone is subconsciously filling in a hole about the moon they could be filling in a whole lot more about more important aspects of the encounter if indeed there was truly an encounter. That's why I'd probably just thank the gentleman nicely for bringing up his encounter and then file it away.

Agreed. A good example of this happened in my field, architectural history. We recently worked on a very high profile site in central PA, home to an early pioneering individual. The alleged date of construction was based upon a story told by an 80 year-old woman who remembers seeing a date stone that read 1754 or something like that. Well, as it turns out, nobody ever actually looked closely at the date stone in question, so her date stuck, and led to the eventual mythology surrounding the site.

Upon further investigation, the date of construction was determined to be MUCH later, thereby throwing off the entire interpretation of the site, and potentially costing them hundreds of thousands of dollars to reinterpret it accurately. All because of a flawed memory or maybe no memory at all.

I would love to go through and evaluate all the reports and analyze them first by date and then by the amount of detail. I bet we could start to weed out some of the more questionable reports that way.

In terms of the date, after all this time it would be easy to get it wrong if relying only on memory. Some people think they remember things better than they actually do, and some people are emphatic that they are right. Some people have a tendancy to fill in details they don't remember. http://en.wikipedia.org/wiki/Confabulation

In terms of perception of time, here's a recent example from myself: While out doing audio recording, I forgot to look at the time on the car radio display before exiting the vehicle and my own watch was disabled due to water intrusion, so I asked an associate what time it was, he said 10:30pm... when it was actually 1:30 am. Consequently, the time and date I recorded *in real time* was incorrect. How could *I* get so confused? Well, stand out in the forest for hours trying not to move, jump in a car and go somewhere else and repeat. The point is that under certain conditions disorientation can occur, and the longer the conditions exist the harder it is to accurately guage time accurately.

I suggest you re-interview, at some point ask why they are sure of the date and time. Don't make too big a deal out of it if a resolution isn't quickly apparent. Instead, see if small details are different between the two interviews. If more than a few small facts are its a strong indicator that the person is just making it up as they go along. Develop some questions ahead of time to help this process along. If they are making it up they may actually get small details wrong during the same interview. Let them provide the details, as they are more likely to remember the answers they give to specfic questions from you as opposed to their own freestyling fabrications. Its important to be subtle and not make your concerns obvious or they will start paying close attention. A really clever, pathological liar probably won't slip up. If they really aren't sure, that may explain it. If the answer is that they are right because they looked at their watch while it was happening and wrote it down on the calender when they got home then there really is a discrepency that is difficult to explain. If the answer is that it was a couple of weeks after someone's birthday (or some other event), the details might be completely right but the year could be incorrect.

I would also suggest double checking to make sure that you have the correct information. You don't want to burn a witness because you accidentally reversed some numbers, looked up the wrong date, or have a faulty reference. Ultimately, you have to assess the witness in terms of reliability, which if you don't find evidence of lying is mostly an intuitional skill. Unless you want to spring for a polygraph... which aren't necessarily reliable. Alternately, have one or more other researchers interview them and go with a consensus decision. If you try this, be very careful to not bias the researchers ahead of time. At most point out the discrepancy, but again don't make too big a deal out of it.

I would just ask the witness straight out. Dont sound like your accusing him or her of anything, just explain your concerns. "I checked the info you gave me in relation to the date and time and the numbers don't jibe, I hope you can understand my concerns and can you offer an explanation?"