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本頁翻譯進度

燈號說明

審定:無
翻譯:羅嘉林(簡介並寄信)
編輯:朱學(簡介並寄信)

這裡有一份課堂講稿,課程由一位客座講師講授。這表明了學生在課堂上應該提問的相關問題類型。


客座講師

Jack Skinner警官,Concord市警察局(譯註:Concord市位於美國北卡羅來納州),警方素描畫家。

問題

素描畫家的注意力放在臉孔的哪些部分?
目前有哪些臉孔回溯系統?
臉孔回溯系統有哪些潛在的限制?

簡歷

居住於Concord 29年,最近6年從事警方合成畫家工作。
退休生活以繪製特徵素描及警方卡通畫為主。
興趣在於藝術以及警察工作。
曾於西北刑事司法學校就學。
參與過多種警方合成畫家課程,包括於聯邦調查局學院,為期三週的臉孔法醫學課程。

甚麼是綜合素描?

將受害者(或目擊證人)的記憶以圖像的方式輸出,從圖像中捉摸目擊者的情緒。
用來作為偵探的工具而不是用來定罪。 法庭偶爾會採用素描,不過只當作傳聞證據。
有助於辨識或排除嫌疑犯。
素描最多只與證人一樣可靠。
由紙上作素描為開始,下一步則從面貌相似人物的照片中指認嫌犯。

時間

除非罪行造成夠大的傷害,記憶很容易褪色。
例外:像強暴這樣的創傷,標準程序是等待24到48小時。
如果證人看見罪犯的時間長一些,有多餘時間形成印象,就會比只是匆匆一瞥提出更好、更正確的描述。

警方素描畫家在哪些案件中提供協助?

大案子-當波士頓環球報提出像「這個案子現在進行的怎麼樣?」的問題時,他們會說警方素描畫家正在努力中。
像謀殺案這種優先偵辦的案件。

素描畫像評分

注意問題的用詞,例如:警察可以依照此畫像在群眾裡找到這個人嗎?vs.可能性有多高?試著提醒證人,對此素描畫像的評分應該依據是否符合他們腦海裡的印象而不是為了取悅素描畫家。
素描畫像評分與所捉捕的對象之間的相關性-素描畫像評分越高表示此畫像與罪犯的相似度越高。

素描畫已經使用過很長一段時間了,從開膛手Jack,Lindbergh綁架犯到Tim McVeigh。

聯邦調查局強調特徵最容易辨識的順序為:
1. 眼睛
2. 頭髮
3. 鼻子
4. 頭型

個人經驗-頭型是最容易辨識的特徵。
耳朵是最不容易辨識的特徵。

證人

最好的證人往往不是慌亂或受創的受害者自己。
在多位證人之中挑選最好的一位,畫下他所描述的。再以這張畫像起始,詢問其他證人的意見。
最好分開訪問每位證人-避免同時集合詢問多位證人時,造成某些證人的態度比其他證人強勢。(朱註:這樣會產生引導作用)

警方合成畫家也是採訪者(請考慮本課程中或許可以稱之為合成畫家)

「認知訪談」- 當證人談論時,你聆聽。
一般而言不會坐在證人對面。
必須使證人感覺放鬆、舒服。
注意問題的用詞,提出可以明確回答的問題以避免引導證人。
背景不要有任何圖片,減少會造成分心的事物。
將受害者的心理狀態帶回犯罪現場,甚至儘可能重回現場。
避免詢問,而要讓受害者自行述說。
給予證人彈性。
不要阻止或打斷證人發言
留意特別有描述能力的部位(例如:眼睛周圍)。

步驟

兩階段s

從事實評量表開始。
問題:「如果你再看到這個人,你能否辨認出他來? 」- 如果答案是「不」,沒有必要繼續素描。
問題:「這個人會不會讓你想到任何人? 」

展示多種特徵的圖片(例如:下巴形狀、鼻型、臉型…等等)。
正面男性特徵可以在聯邦調查局的臉孔圖譜內找到,這些相片來自警方檔案照以及聯邦調查局幹員的照片。目前正試圖建構女性特徵的圖譜。
如果有任何相似性,請受訪者指出。
從頭型開始。

正面相片

聯邦調查局的臉孔圖譜內的相片都是正面的。
大部分素描都是正面的,但是也有側面觀的。

電腦程式

Faces
Mac-a-Mug

關於性別差異的個人經驗

女性比較難描繪。
女性較擅長描述嫌犯的特徵,或許跟平常化妝的經驗有關。
年輕人(13~14歲)比成人容易描繪。

Yuri 的訪談描繪經驗

由訪談中得來的素描畫像
改變髮型,讓臉形更圓潤,讓面容看起來年輕一點,好看一點,眼眶深一點,加上一些狡猾的笑容。
也要參考第二位證人的描述。
Yuri:些許細節較不清楚,但是已經盡可能描述所有特徵。




Here is an example of a lecture note for a class with a guest lecturer. It indicates the kind of relevant questions students must ask in class.


Guest Presenter

Officer Jack Skinner, Concord Police Department, police sketch artist.

Questions

What aspects of a face does a sketch artist pay attention to?
What face recall systems exist?
What are the potential limitations of face recall systems?

Brief Biography

29 years at Concord, last 6 years working as a police composite artist.
Does character sketches for retirements, police cartoonist.
Interest in art and police work.
Attended the Northeastern School of Criminal Justice.
Has taken various police composite artist courses, including a 3-week facial forensics course at the FBI academy.

What is a Composite Sketch?

Graphic rendering of the victim's (or witnesses') memory, get the emotions of the witness captured in the image.
Tool for the detective, not used for convictions. Occasionally, sketches are brought in to court, but they are considered hearsay evidence.
Useful for identification purposes or elimination of suspects.
Sketch is only as good as the witness.
Starting point on paper. The next step would be a photo lineup of similar-looking people.

Time

Unless the crime is traumatic enough, the memory will fade.
Except very traumatic events: for example, in rape cases, standard to wait 24-48 hours.
If the witness saw the perpetrator for a longer period of time, have more time to formulate image and give better, more accurate descriptions than if just saw briefly.

For what kind of Cases are the Services of a Police Artists Requested?

Big cases – when the Boston Globe asks questions like 「What have you been doing on the case?」 they can answer that they've got a police artist working.
High priority crimes, such as murder.

Sketch Ratings

Word question carefully. e.g. Can the officer pick the person out of a crowd with this picture? vs. How good is this? Try to remind witness this is their picture so they don't try to just please the artist.
Occasional correlation between the rating and the apprehended person – high rating usually a pretty good likeness of the perpetrator.

Sketches have been used for a very long time. From Jack the Ripper to the Lindbergh kidnappers to Tim McVeigh.

FBI claims for the rank of most recognizable features:
1. Eyes
2. Hair
3. Nose
4. Head shape

Personal experience- head shape is the most recognizable.
Least recognizable features: ears.

Witnesses

Best witness is not always the victim, who may be too flustered or traumatized by the event.
With multiple witnesses, figure out who would be the best witness and draw their description. Then, starting with that image, get opinions of the other witnesses.
Best to interview multiple witnesses separately- could have problem of one being more dominant than others if they're all in the same room.

Police Composite Artist is Also an Interviewer.

"cognitive interview" – witness talks, you listen.
Generally don't sit across from witness.
Must relax the witness, make them comfortable.
Word questions carefully, ask open-ended questions so as not to lead the witness.
No pictures in the background, few distractions.
Bring victim mentally back to the scene Have victim sketch the scene. If possible, bring back to actual scene.
Let victim give the information rather than ask for it.
Be flexible with witness.
Don't stop or interrupt.
Stay in particular descriptive regions (e.g. eye area).

Process

2 phases

Start with fact sheet.
Ask 「If you saw this person again, could you identify him?」- if no, then no point in going on with sketch.
Ask 「Does person remind you of anyone?」

Show pictures of various features (e.g. chin shape, nose type, face shape, etc).
FBI face book contains frontal male features from mugshots and pictures of FBI workers. Currently trying to get a female face book as well.
If anything looks similar, point it out.
Start with head shape.

Frontal Images

Images in FBI face book all frontal.
Most sketches are frontal, but there have been a few side views.

Computer Programs

Faces
Mac-i-Mug

Personal Experience Involving Class Differences

Females more difficult to draw.
Women better at describing- may involve application of makeup.
Young (13-14 year olds) better than adults.

Yuri's Mugger

Sketch evolved during the interview.
Hair changes, rounded out face, make the face look younger, nicer, deeper eye sockets, added smirk.
Second witness description as well.
Yuri: something was slightly off, but had already described all the features possible.




 
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