Today I'm going to talk about some serious stuff,

今天我們要談一些嚴肅的事情

and then hopefully, we'll have a little bit of humor along with it.

然後希望在這當中能摻雜些幽默

I brought some props.

我帶了一些道具來

I'm going to need some help from some people in the front row to commit a crime.

我會需要坐在前排的一些人幫我完成一個犯罪

(Laughter)

（笑聲）

And for the serious part, I'm going to be talking about DNA errors,

至於演講中嚴肅的部分，我將會談到DNA錯誤

forensic DNA errors today.

現今法證DNA的錯誤

So imagine

那麼開始想像

- and I'm only going to ask you to imagine this briefly -

我只會要求你們短暫的想像一下

a loved one is hurt or killed in a crime.

你的摯愛在一場犯罪中受傷或者被殺害了

Someone's finally arrested, you go through the endless trials,

終於有人被逮捕了，你也歷經了無止盡的審判

and someone is incarcerated for the crime.

而那人也因為犯法而被監禁

You think you're done with it.

你也以為這件事就此落幕

Twelve years, 20 years later, you hear they got the wrong person.

12年、20年以後，你聽說他們抓錯了人

That's the kind of thing that we are trying to avoid.

這樣的事情是我們試圖避免的

And so, in order to do that,

就這樣，為了達到這個目的

we have to constantly be looking at our techniques

我們必須不停的檢視我們的技術

to see how to improve them.

看如何改善他們

So I'm going to talk about some issues in my own field that I've seen in my work.

所以接下來我會談一些我在我工作領域見到的問題

I work in all 50 states now,

我的工作地點廣布50個州

I have cases overseas: Asia, Africa, Europe.

我有海外的案件：亞洲、非洲、歐洲

And some of the things I've seen that I'm concerned about,

我所見的某些事情令我感到擔憂

that I have raised at professional meetings,

這些事情我也曾在專業的會議中提過

some of it has never been shown before, and I'll show you tonight.

有些則未曾展現在世人面前，而今天我會告訴大家

So we're talking about forensic DNA errors.

那麼我們即將談到法證DNA的錯誤

I don't want to you to think it's all bad,

我不想讓你們認為這都是糟糕的東西

it's not all bad, it's a great field, it's my life.

不全是壞的，這是個很棒的領域，這是我的人生

And I'm going to break it into two categories:

而我將把今天的演講分為兩個類別

one is statistical and interpretative errors,

一個是統計和釋義錯誤

so things where the conclusions are wrong, based on human reasoning and mathematics,

這些錯誤是依據人類和數學上的解釋所造成結論的錯誤

and the other one is contamination, which is kind of easy to understand.

而另一項是汙染，這是很容易理解的

Somebody spills some DNA while it gets transferred,

某個人在轉送的過程中濺出了一些DNA

and then I'll tell you what my lab here in Boise is working on

接下來我會簡短的告訴你們我Boise的實驗室在從事

in the contamination area very briefly.

有關污染方面的什麼工作

So we'll have a first slide, I'm going to turn you into the DNA experts.

那麼我們看第一張投影片，我會把你們變成DNA的專家

Get ready for science, here it goes.

準備好接觸科學了，現在開始了

This is the easy stuff, this is a single source,

這事情不難，這是個單一來源

I can teach you guys to do this immediately.

我可以立刻教你們如何做這件事

Let's say I decide I'm going to commit a crime with this.

讓我們假設我決定用這個東西犯罪

It's clean, it just got out of the dishwasher,

他是乾淨的，剛從洗碗機裡拿出來的

and there was bleach in the dishwasher, so it has no DNA on it.

而洗碗機裡有漂白水，所以上面沒有DNA

I touch it, and I go to the front row, and I commit a murder.

我觸碰了它，然後我走到前排，進行一場犯罪

The police come, they do the spatter,

警察來了，他們做了血液噴濺分析

they collect some of the blood to identify the victim,

他們收集一些血液以便識別受害者

they see my fingerprint, and they --

他們看到了我的指紋，然後他們...

I always carry a swab.

我總是攜帶棉籤

(Laughter)

（笑聲）

I really do always carry --

我真的總是攜帶...

They take a swab, they swab it, and what's really nifty about these swabs

他們拿了一個綿籤並且擦拭它，而這些綿籤絕妙的地方在於

is you can just knock the ends off of them,

你可以將兩端的棉花碰掉

but I'm going to pull it, and put it in here.

但我現在將它扯掉，然後放在這裡

I should be wearing gloves etc., etc.

我應該要戴手套...等等

(Laughter)

（笑聲）

OK.

好

Now, the issue is am I the murderer?

現在，問題在於我是殺人兇手嗎？

Here I am, the suspect,

我就在這，一個嫌疑犯

and all you have to know about DNA is

最重要的一點

you get it from your mother and your father.

是你的 DNA 遺傳自父母親

So that means that every location on the DNA that I'm going to look at

這表示我們即將要看到DNA上的每一個點

- and I've shown you these are four locations here, in the columns;

而我將這四個位置呈現在這些欄位中

sorry that this is a little off -

抱歉這有點不太靈光

at every location you've got one number from mom, one number from dad.

每個位置中，你從母親那裡得到一個數字，從父親那裡得到一個數字

I've got one number from my mom, one from dad, I'm the suspect.

我從我母親那裡得到一個數字，從我父親那裡得到一個數字。我是個嫌疑犯

Am I a match?

我符合配對嗎？

(Audience) Yes.

（觀眾）是的

Greg Hampikian: My students, when I say the word 'match',

Greg Hampikian：我的學生們，當我說到＂配對＂這個詞的時候

have to say 'statistics'.

必須說＂統計數字＂

So, am I a match?

那麼我符合配對嗎？

(Audience) Statistics.

（觀眾）統計數字

GH: At this level,

GH：在這個程度下

maybe one in 10,000 people would be included in this match,

大約有一萬分之一的人會符合配對

maybe one in 2,000, something like that.

大約兩千分之一之類的

Alright, that's a single source, everybody gets it right.

好的，那是單一來源，每個人都能處理的正確

Next.

接下來

Here is a mixture.

是一個混合

How do we get a mixture?

我們如何德到一個混合？

Before I commit the crime, a couple of other people I offered--

在我犯罪之前，我給了其他幾個人--

touch this, maybe three of you.

摸這個，或許你們當中的三個人

So now, they come in, and they do the swab, and they get a mixture.

那麼現在，他們進來了並且用棉籤採取DNA，然後他們就得到了一組混合

This is what they get: these again are four locations of DNA,

這就是他們得到的東西：這些是DNA的四個點

but now, there is a bunch of what we call alleles or sizes in there.

但現在，在這裡面有一些我們稱為等位基因或尺寸的東西

The question becomes, "Am I included in that?"

問題就變成了＂我被包含在內嗎？＂

So, am I still included, or are all of my sizes in there?

那麼，我仍然被包含在內嗎或我所有的尺寸都在內嗎？

(Audience) Yes.

（觀眾）是的

GH: Is it a match? (Audience) Yes.

GH：那是正確的匹配嗎？ （觀眾）是的

GH: The statistics is now something like one in 10 or maybe one in 50.

GH：統計數字現在大約是十分之一或大概五十分之一

And that's because more people could potentially be included.

而那是因為更多的人有被包含在內的潛在性

Now, you think that this would be an easy concept,

現在，你認為這會是個簡單的概念

we'd have mathematics that can deal with it,

我們有數學能夠處理這些東西

but when laboratories are given the same data,

但當實驗室收到相同的數據時

they'd sometimes vary in that statistic over ten to the 10.

他們的差異會超過十的十次方倍

That's the difference between going to court and say,

這差異就如同到法院然後說

"There was 30 dollars of damage to my car,"

＂我的汽車的損壞賠償金是30圓＂

and "The damage to my car was greater

和＂我的汽車的損害賠償金大於

than the combined gross domestic product of every country

每個國家的國內生產總值

over the last 100 years" and then sum.

在過去一百年內＂然後再加總

(Laughter)

（笑聲）

So the statistics are done differently in different labs,

不同的實驗室有不同的統計方式

and they give a very different impression based on how the statistics worked before.

而依據以往統計優劣與否的經驗，他們會給出不同的見解

This mixture question becomes very complicated,

這個混合問題會變得十分複雜

and if you give a mixture to ten experts,

如果你將一個混合給十個不同的專家

you might get ten different interpretations.

你可能會得到十個不同的解釋

I did that.

我曾做過這種事

I took a mixture case from Kerry Robinson,

我接了Kerry Robinson的混合案件

a man who wrote to me, and who says he's innocent,

這個男人寫信給我並告訴我他是無辜的

and he was convicted in a gang rape in Georgia.

他在喬治亞州的一場輪姦案中被判有罪

There were three men who raped a woman.

當時有三個男人性侵害了一個女人

One man was identified,

一個男人被指認出來了

all of his DNA in the semen was recovered from the victim.

在受害者身上找到了他精液裡的所有DNA

She picked him out of a yearbook.

她在一本畢業紀念冊中認出了他

He's given an option to reduce his sentence:

他得到了一個能減刑的選擇：

tell us who one of the other guys is.

告訴我們當中的另一人是誰

He makes up a name, the guy doesn't exist.

他捏造了一個名字，那個人並不存在

They say, "No deal."

他們說＂不成＂

Then he says, "Kerry," and he can't remember the last name.

然後他說＂Kerry＂而他記不得姓氏了

"Robinson," he finally says.

＂Robinson＂他最後說

And so they arrest Kerry Robinson, the guy he knew in high school.

然後他們逮捕了Kerry Robinson，他在高中認識的人

Kerry says, "He only gave my name

Kerry說＂他說出我的名字

because he thinks I talked to the cops about him."

只是因為他認為我跟警察說了他的事＂

But, because he gave a name, his sentence is reduced.

但是，因為他說出了名字，他得到減刑了

That man, the first man is out of prison right now.

那個男人，第一個男人現在已經出獄了

Kerry Robinson is in prison.

Kerry Robinson在坐牢

I looked at the DNA, I say,

我看了DNA然後說

"Kerry Robinson is excluded from that mixture."

＂Kerry Robinson不包含在那個混合中＂

I took the same data, me and Itiel Dror my co-author,

我帶著相同的數據，我和我的合著者Itiel Dror

and we gave it to 17 analysts at the same lab, another lab

而我們將數據給了17個同一間實驗室的化驗員，另一個實驗室

- sorry, we all work in one lab,

抱歉，我們都在同一間實驗室工作

but not the first lab that did the DNA -

但不是做DNA檢驗的第一間實驗室

and we asked them, "Is it a match? Is he excluded?"

然後我們問他們＂符合配對嗎？他排除嫌疑了嗎？＂

- you didn't say statistics -

你們沒有說＂統計數字＂

GH: Is it a match? (Audience) Statistics.

GH：符合配對嗎？ （觀眾）統計數字

GH: Alright, you got a pass.

GH：好的，你們通過了

Is it a match? Is he excluded? Thank you.

符合配對嗎？他被排除嫌疑了嗎？ 謝謝你們

Or is it inconclusive?

或是不能確定？

We gave it to 17 experts,

我們把數據給了17個專家

all trained, in one lab in North America, all part of a state lab.

每個都在北美的一個實驗室裡受過訓練，每個都是州立實驗室的一部份

We got all three answers.

我們三種答案都得到了

Not only we got all three answers but only one of the people at that lab

我們不僅三種答案都得到了而且只有實驗室中的一人

agreed with the lab in Georgia's original conclusion

同意喬治亞州中做出原結論的實驗室

that Kerry was included.

這個結論是Kerry被包含在嫌疑人中

Next, we got a little attention for that, and new scientists picked it up,

接下來，我們因此得到了一些關注，然後新的科學家繼續研究

and economists picked it up, but it's still a problem.

還有經濟學家繼續研究，但問題仍然沒有解決

All right, I was trying to explain this mixture question to a prosecutor

好，我試著向一個檢察官解釋這個混合問題

over the summer, so I had to use some scrabble tiles.

在夏季的時候，那麼我得用一些拼字遊戲磚解釋

And what I said is a mixture

而我說一個混合

is like if you put my name and your name, Mr. Prosecutor, in a bowl.

就如同你將我的名字和你的名字，檢察官先生，放進一個碗裡

We put two people in, but you can pull lots out.

我們放進了兩個人名，但你可以得到很多人名

And so I had to do --

就這樣我必須做...

I took our two names and these are the letters for our two names.

我拿了我們兩個名字的磁磚，而這些是組成我們兩個名字的字母

Now, we'll get into this question of subjectivity and bias.

現在，我們即將進入主觀性和成見的問題

Who contributed names to this?

誰的名字可以被這個拼出來？

I've told you, I did it.

我已經告訴你了，我的可以

You might not know how to spell my name.

你們可能不知道怎麼拼我的名字

But Al Gore did too, didn't he?

但Al Gore也可以，不是嗎

George Will, Larry King, Mary Kay, Porky Pig, Anne Klein, Henry Miller,

George Will、Larry King、 Mary Kay、Porky Pig、 Anne Klein、 Henry Miller

Happy Gilmore, Lina Horne, Papa Gino, Pepe Le Pew, Marilyn Monroe,

Happy Gilmore、 Lina Horne、Papa Gino、 Pepe Le Pew、 Marilyn Monroe

Willy Wonka, Rainman, King Phillip, King Lear, King Kong, etc.

Willy Wonka、 Rainman、 King Phillip、 King Lear、King Kong...等等

The point is these mixtures,

重點是這些混合物

even though we go to court, and they say that is the person a match

即便我們上了法庭，然後他們說這個人符合配對

(Audience) Statistics.

（觀眾）統計數字

the statistics can widely, widely, widely vary

統計數字的差異可以到非常大

to the point where they can become meaningless,

大到這些統計數字會變得沒有意義

and there is no uniformity in my field for that.

而對此，在我的領域當中沒有均一性

Next slide.

下一張投影片

This is just some of the attention we got for that article.

這些只是我們因為這篇文章吸引到的一些注意力

And I'll take the next one.

而我要講下一張投影片

Here is another problem of statistics.

這是統計數字的另一個問題

This is a very unfortunate case.

這是一個非常不幸的案例

Mr. Denman became a missing person.

Denman成為了失蹤人口

This is from the Albuquerque newspaper, this is his obituary,

這是他的訃聞，取自於Albuquerque報紙

he was 49 years old when he left us, and donations can be sent, etc.

他離開我們的時候49歲，然後捐款會給...等等

There is another article about this later, when they interviewed his brother,

在這之後還有一篇關於這件事的文章，當他們訪問他的兄弟時

because they found the bones near the house,

因為他們在房子附近找到了他的骨頭

and they thought it was a murder.

然後他們認為這是一場謀殺案

FBI came in to identify, "This is Donnie Denman,"

FBI介入並鑑定＂這是Donnie Denman＂

with DNA they identified it,

他們依DNA鑑定的

so there is another article looking for people who could help solve the murder.

所以又有一篇為了尋找幫助破案的人的文章

Next slide.

下一張投影片

This is now four months later.

這是四個月之後

Donnie is not dead.

Donnie沒有死

His friend was putting newspapers down to his parents' car in the garage,

他的朋友將報紙放入他父母放在車庫的車中

saw that there is an obituary for Donnie Denman,

然後看到Donnie Denman的訃聞

and that there was a funeral, called Donnie Denman and said,

而且發現已經舉辦了葬禮，於是打電話給Donnie Denman然後說

"They think you're dead," and he said, "Who gave the oration?"

＂他們以為你死了＂然後他說＂是誰做的葬禮演講？＂

He said, "Your pastor."

他說＂你的牧師＂

He called the pastor, he straightened it out.

他打給了牧師然後澄清了這件事

This shows you that even though there was a DNA match, right,

這告訴你們，即便DNA符合配對，對了

a FBI DNA match --

一個FBI做出的DNA配對

People.

人們

(Laughter)

（笑聲）

Even though there was a match--

即便符合配對

(Audience) Statistics.

（觀眾）統計數字

the statistic wasn't that high, this is mitochondrial DNA,

這個統計數字不是那麼高，這是粒線體的DNA

a particular type of DNA, we use on old bones, broken hair etc.

一種特別的DNA，我們用在老的骨頭，斷掉的頭髮...等等

And it doesn't give us those powerful statistics.

這不會給我們那些有力的統計數字

Next slide please.

請換下一張投影片

This is our last story of statistics, this was my first case in Taiwan.

這是統計數字的最後一個故事，這是我在台灣的第一個案件

And this is for the Taiwan Innocence Project.

而這事關於台灣無辜計畫的

They heard from a man "Mr Chen".

他們從一個叫＂陳先生＂的男人那裡聽到的

So I'm going to show you how to read this.

我來告訴你們怎麼理解這個

This is now Y-chromosome DNA,

這是DNA的Y染色體

so most of the columns will just have one number.

所以大部分的欄位中只會有一個數字

I'm sorry you can't see it that clearly,

抱歉你們無法看得很清楚

but this is DNA recovered from semen from the underwear of a rape victim.

但這是從一個性侵害受害者內褲上的精液得到的DNA

She was raped by three men, and these are the alleles or DNA sizes

她被三個男人性侵，而這些是等位基因或DNA尺寸

that were found.

這是被我們找到的

This is Mr. Chen.

這是陳先生的數據

Now is Mr. Chen's 15 there? Yes.

現在，陳先生的15號在嗎？是的

In fact, every one of Mr. Chen's alleles is there.

事實上，陳先生的每一個等位基因都在

Mr. Chen is arrested, Mr. Chen is convicted,

陳先生被逮捕了並且被判有罪

he loses all three appeals, he writes the Taiwan Innocence Project.

他三審都輸了，所以他寫信給台灣無辜計畫

They needed me when they came over to stage, show me the state,

他們需要我，當他們來展現並告訴我狀況時

and they say, "What can we do, what's the statistic on this?"

他們說＂我們能做什麼，這件事的統計數字是什麼？＂

And we try to calculate the statistic, it was pretty strong.

然後我們試著算統計數字，這些統計數字蠻強大的

I said, "But there are new tests."

我說＂但有新的化驗＂

So they went to court in Taiwan, and they got a test

所以他們回到台灣的法庭，然後做了一個新化驗

that instead of looking at the number of alleles in the first kit,

這個化驗不是只審視第一套工具中的等位基因數

added some other alleles, some other markers in this kit to look at.

而是加了一些其他等位基因，這套工具中其他用來審視的特徵

So they looked at more locations, more powerful statistics.

所以他們審視了更多點，更有力的統計數字

Even though he was included

即便他被包含在嫌疑人中

with the less powerful statistics,

伴隨著比較無力的統計數字

with the more powerful, - here is Mr. Chen -

伴隨著比較有力的--這是陳先生的數據--

his 17 is not in the underwear,

他的17號並不在內褲中

his 13 is not in the underwear.

他的13號不在內褲中

Next slide.

下一張投影片

This is Mr. Chen in March of 2014.