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翻译:罗嘉林(简介并寄信)
编辑:朱学恒(简介并寄信)

这里有一份课堂讲稿,课程由一位客座讲师讲授。这表明了学生在课堂上应该提问的相关问题类型。


客座讲师

Jack Skinner警官,Concord市警察局(译注:Concord市位于美国北卡罗来纳州),警方素描画家。

问题

素描画家的注意力放在脸孔的哪些部分?
目前有哪些脸孔回溯系统?
脸孔回溯系统有哪些潜在的限制?

简历

居住于Concord 29年,最近6年从事警方合成画家工作。
退休生活以绘制特征素描及警方卡通画为主。
兴趣在于艺术以及警察工作。
曾于西北刑事司法学校就学。
参与过多种警方合成画家课程,包括于联邦调查局学院,为期三周的脸孔法医学课程。

什么是综合素描?

将受害者(或目击证人)的记忆以图像的方式输出,从图像中捉摸目击者的情绪。
用来作为侦探的工具而不是用来定罪。 法庭偶尔会采用素描,不过只当作传闻证据。
有助于辨识或排除嫌疑犯。
素描最多只与证人一样可靠。
由纸上作素描为开始,下一步则从面貌相似人物的照片中指认嫌犯。

时间

除非罪行造成够大的伤害,记忆很容易褪色。
例外:像强暴这样的创伤,标准程序是等待24到48小时。
如果证人看见罪犯的时间长一些,有多余时间形成印象,就会比只是匆匆一瞥提出更好、更正确的描述。

警方素描画家在哪些案件中提供协助?

大案子-当波士顿环球报提出像“这个案子现在进行的怎么样?”的问题时,他们会说警方素描画家正在努力中。
像谋杀案这种优先侦办的案件。

素描画像评分

注意问题的用词,例如:警察可以依照此画像在群众里找到这个人吗?vs.可能性有多高?试着提醒证人,对此素描画像的评分应该依据是否符合他们脑海里的印象而不是为了取悦素描画家。
素描画像评分与所捉捕的对象之间的相关性-素描画像评分越高表示此画像与罪犯的相似度越高。

素描画已经使用过很长一段时间了,从开膛手Jack,Lindbergh绑架犯到Tim McVeigh。

联邦调查局强调特征最容易辨识的顺序为:
1. 眼睛
2. 头发
3. 鼻子
4. 头型

个人经验-头型是最容易辨识的特征。
耳朵是最不容易辨识的特征。

证人

最好的证人往往不是慌乱或受创的受害者自己。
在多位证人之中挑选最好的一位,画下他所描述的。再以这张画像起始,询问其他证人的意见。
最好分开访问每位证人-避免同时集合询问多位证人时,造成某些证人的态度比其他证人强势。(朱注:这样会产生引导作用)

警方合成画家也是采访者(请考虑本课程中或许可以称之为合成画家)

“认知访谈”- 当证人谈论时,你聆听。
一般而言不会坐在证人对面。
必须使证人感觉放松、舒服。
注意问题的用词,提出可以明确回答的问题以避免引导证人。
背景不要有任何图片,减少会造成分心的事物。
将受害者的心理状态带回犯罪现场,甚至尽可能重回现场。
避免询问,而要让受害者自行述说。
给予证人弹性。
不要阻止或打断证人发言
留意特别有描述能力的部位(例如:眼睛周围)。

步骤

两阶段s

从事实评量表开始。
问题:“如果你再看到这个人,你能否辨认出他来? ”- 如果答案是“不”,没有必要继续素描。
问题:“这个人会不会让你想到任何人? ”

展示多种特征的图片(例如:下巴形状、鼻型、脸型…等等)。
正面男性特征可以在联邦调查局的脸孔图谱内找到,这些相片来自警方文件照以及联邦调查局干员的照片。目前正试图建构女性特征的图谱。
如果有任何相似性,请受访者指出。
从头型开始。

正面相片

联邦调查局的脸孔图谱内的相片都是正面的。
大部分素描都是正面的,但是也有侧面观的。

计算机程式

Faces
Mac-a-Mug

关于性别差异的个人经验

女性比较难描绘。
女性较擅长描述嫌犯的特征,或许跟平常化妆的经验有关。
年轻人(13~14岁)比成人容易描绘。

Yuri 的访谈描绘经验

由访谈中得来的素描画像
改变发型,让脸形更圆润,让面容看起来年轻一点,好看一点,眼眶深一点,加上一些狡猾的笑容。
也要参考第二位证人的描述。
Yuri:些许细节较不清楚,但是已经尽可能描述所有特征。




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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