英検長文問題対策〜記憶をめぐって〜(2)

利根川先生も誤った記憶によって無実の人が罪になる危険性を挙げていましたが、記憶に基づく証言の危険性を研究し、自ら証言もしてきたElizabeth Loftusという研究者をNatureは大きく取り上げていました。ポッドキャストもあり充実した記事になっています。

Evidence-based justice: Corrupted memory
Elizabeth Loftus has spent decades exposing flaws in eyewitness testimony. Her ideas are gaining fresh traction in the US legal system.
Moheb Costandi
14 August 2013

At Pacely's trial a few months later, memory researcher Elizabeth Loftus testified on his behalf. She told the jury how memory is fallible; how stress and fear may have impaired Mrs M's ability to identify her assailant, and how people can find it difficult to identify someone of a race other than their own.

Pacely was acquitted. “It's cases like this that mean the most to me,” says Loftus, “the ones in which I play a role in bringing justice to an innocent person.”

被害者の証言の信憑性を疑うことになるので、批判を浴びるのは予測できそうです。訴えられたり、脅迫されてきたこともあるそうですが、彼女の見識はニュージャージー州の法制度に取り入れられるようになっているそうです。

Her work has earned her plaudits from her peers, but it has also made her enemies. Critics charge that in her zeal to challenge the veracity of memory, Loftus has harmed victims and aided murderers and rapists. She has been sued and assaulted, and has even received death threats. “I went to a shooting range to learn how to shoot,” she says, noting that she keeps a few used targets in her office as a point of pride.

Now, the 68-year-old scientist's research is starting to bring about lasting changes in the legal system. In July last year, the New Jersey Supreme Court issued a ruling — based largely on her findings — that jurors should be alerted to the imperfect nature of memory and the fallibility of eyewitness testimony as standard procedure. Loftus is working with judges in other states to make such changes more widespread.

記憶のあいまいさについては以下の例が分かりやすかったです。質問の仕方でも答えが変わってきてしまうというのです。

Following that lead, Loftus won funding in 1974 for a proposal to study witness accounts of accidents, and she soon published the first of several influential studies revealing the limitations of eyewitness testimony1. She showed people film clips of car accidents and asked them to estimate the speed of the cars. The wording of the questions, she found, had a profound effect on the estimates. People who were asked, “How fast were the cars going when they smashed into each other?” gave higher estimates on average than those with whom the verb 'hit' was used. And those who were told that the cars had 'contacted' each other gave the lowest estimates.

Those asked about cars smashing into one another were more than twice as likely as others to report seeing broken glass when asked about the accident a week later, even though there was none in the video. “I realized that these questions were conveying information,” says Loftus. “I began to think of it as a process of memory contamination, and we eventually called it the misinformation effect.”

幼いときのトラウマの記憶についても彼女は疑問視しているようですが、ここでも他の研究者から非難を浴びているようです。しかし、彼女はwhen an innocent person is accused, we have a whole new set of victims, and I'm more horrified by an innocent person getting convicted than by a guilty person being acquitted.という信念に支えられているようです。

Ross Cheit, a political scientist at Brown University in Providence, Rhode Island, started the Recovered Memory Project in 1995 to document and respond to what he says has been a one-sided debate. There are now more than 100 corroborated cases of recovered memory on his website (http://blogs.brown.edu/recoveredmemory), he says, including some on which Loftus had consulted.

“Loftus is often on the losing side, and she's sometimes wrong in a spectacular way,” Cheit says. Her testimonies, he adds, can be psychologically damaging for the victims. “If you're telling someone you think their memories are false, when they have corroborating evidence that they were abused, that's corrosive.”

Loftus does not believe that Cheit's site corroborates recovered memories. “He might have some cases of people who didn't think about their abuse for some time and were reminded of it, but as for actual repression, no,” she says. “I cringe at the idea of hurting genuine victims, but when an innocent person is accused, we have a whole new set of victims, and I'm more horrified by an innocent person getting convicted than by a guilty person being acquitted.”

自らの不安からか僕たちは早く犯人が見つかり、裁かれてほしいと願ってしまいます。でも、拙速な裁判は無実の人を罪人にしてしまう可能性もあるんですよね。