科学美国人60秒 SSS 法医学真的科学吗（在线收听）

Forensic Science: Trials with Errors 法医学真的科学吗

“We have increasing doubts about this evidence, but we don’t feel yet that we have the scientific knowledge and basis to exclude it altogether.”

“虽然对这一证据的怀疑日渐加深，但我们仍感觉还没有足够的科学知识和依据对其进行完全排除。”

Jed Rakoff, United States District Judge for the Southern District of New York. He spoke about forensic evidence—and the need for it to actually be based in science—at the annual meeting of the American Association for the Advancement of Science in Boston on February 18th.

杰德·雷科夫（Jed Rakoff），纽约南部地区的一名美国地区法官。2月18日，在波士顿召开的美国科学促进会年会上，他谈到了法医证据，以及对其拥有确切科学依据的需要。

\In 2009 the National Academy of Sciences issued a report critical of a lot of the forensic evidence in the courtroom.

2009年，美国国家科学院(National Academy of Sciences)发表了一份报告，对法庭上大量的法医证据进行了批评。

“Most fundamentally…the report said that what was really lacking was testing and research. And thus they questioned whether any of this could be called science and they also questioned whether it was really that accurate…

“最根本的是……报告中指出法医证据真正缺乏的是测试和研究。因此他们质疑这是否可以被称为科学，以及它是否真的那么准确……

But forensic evidence is still widely admitted, even when the science behind it may be lacking.

但是法医证据仍然被广泛地承认，即使它背后缺乏科学依据。

I think courts continue, despite their doubts, to admit this evidence…and that is still the feeling…that, eh, it’s still better than nothing, it’s still useful evidence, it has some degree of objectivity that’s not present in much lay testimony. And therefore it is useful. The problem of course is it comes heralded as science, and that gives it a weight that is probably disproportionate.

我认为尽管法院存有疑虑，但他们仍继续承认这些证据……可能仍然感觉有证据总比没有好。它仍然是有用的，有一定的客观性，而且它是很多证词中都无法呈现的。因而，它仍然很有用。当然问题是，它被称为科学，而这给了它不太相称的权重。

I had a case, this was before the National Academy report, but it’s sort of illustrative of what I’m talking about…United States versus Glynn. In that case, the government put on a tool-mark expert to testify that the markings on the shell that had been found at the scene of the crime matched the markings inside the barrel of the gun that had been found under the defendant’s bed…and I asked him, for example, what’s your error rate and what’s the error rate of this methodology that you’re using. And he said zero. And I said zero? And he said yes. And I said how can it be zero. And he said well, in every case I’ve testified, the guy’s been convicted.”

在国家科学院发表该报告前，我曾遇到过一个案例，它或许能在某种程度上解释我所说的观点……美国政府对质一位叫格林的被告。在那个案例中，政府派出一位工具痕迹鉴定专家，请他鉴定在案发现场发现的弹壳上的痕迹，是否与被告床下发现的枪支枪膛里的痕迹相匹配。我当时问他，比如问道，你的失误率是多少？你使用的这种方法的失误率又是多少？他答道，是零。我当时就反问，是零？他说是的。我又说道，怎么可能是零呢。他则回答称，就他鉴定的案例而言，他就是会被判有罪。