Memory is a net; one finds it full of fish when he takes it from the brook; but a dozen miles of water have run through it without sticking. Oliver Wendell Holmes, Sr.
Can we trust our memories? I recently got into a heated discussion with a friend about the details of an event in which we both participated. She became very angry that the version I remembered was different than what she remembered. Neither one of us wanted to budge from our position.
Beginning the discussion, I had some questions about how things really happened, but her version contradicted what I was sure had happened. The more she protested, the more amazed I became: not at the difference in details, but in the sureness each of us had of having the "right" recollection.
And yet, after she hung up on me, I mulled over the conversation for several hours, and conceded that her version could be right.
And that frightened me. How vulnerable we are to suggestion, and how easy it is to incorporate someone else's version of what they saw or think they saw!
When my husband did aircraft accident investigations, he learned that everyone saw something different in the event, often conflicting with each other. The reliability of eyewitness reports also has an impact in criminal cases. For a further discussion on this impact, see How Reliable is Eyewitness Testimony?: A Decision By New York State's Highest Court Reveals Unsettling Truths About Juries by Michael C. Dorf and The Problem with Eyewitnesses by Finlo Rohrer of BBC News.