Sunday, March 31, 2013

Circumstantial evidence


Circumstantial evidence is evidence in which an inference is required to connect it to a conclusion of fact, like a fingerprint at the scene of a crime. By contrast, direct evidence supports the truth of an assertion directly—i.e., without need for any additional evidence or the intervening inference.
http://en.wikipedia.org/wiki/Circumstantial_evidence 
On its own, it is the nature of circumstantial evidence for more than one explanation to still be possible. Inference from one piece of circumstantial evidence may not guarantee accuracy. Circumstantial evidence usually accumulates into a collection, so that the pieces then become corroborating evidence. Together, they may more strongly support one particular inference over another. An explanation involving circumstantial evidence becomes more valid as proof of a fact when the alternative explanations have been ruled out.
Circumstantial evidence allows a trier of fact to deduce a fact exists.[1] In criminal law, the inference is made by the trier of facts in order to support the truth of assertion (of guilt or absence of guilt).
Testimony can be direct evidence or it can be circumstantial. If the witness claims they saw the crime take place, this is considered direct evidence. For instance, a witness saying that the defendant stabbed the victim is direct evidence. By contrast, a witness who says that she saw the defendant enter a house, that she heard screaming, and that she saw the defendant leave with a bloody knife gives circumstantial evidence. It is the necessity for inference, and not the obviousness of a conclusion, that determines whether or not evidence is circumstantial.
Forensic evidence supplied by an expert witness is usually circumstantial evidence. A forensic scientist who testifies that ballistics proves the defendant’s firearm killed the victim gives circumstantial evidence from which the defendant’s guilt may be inferred. (Note that an inference of guilt could be incorrect if the person who actually fired the weapon was somebody else.)
On the other hand, the additional circumstantial evidence of the defendant's fingerprint on the trigger would dovetail with this piece to provide corroborating evidence.
The two areas in which circumstantial evidence is of most importance are civil and criminal cases where direct evidence is lacking.

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[edit]Civil law

Circumstantial evidence is used in civil courts to establish or refute liability. It is usually the most common form of evidence, for example in product liability cases and road traffic accidents. Forensic analysis of skid marks can frequently allow a reconstruction of the accident. By measuring the length of such marks and using dynamic analysis of the car and road conditions at the time of the accident, it may be found that a driver underestimated his or her speed. Forensic science and forensic engineering are common as much in civil cases as in criminal.

[edit]Criminal law

Circumstantial evidence is used in criminal courts to establish guilt or innocence through reasoning.
With obvious exceptions (immature, incompetent, or mentally ill individuals), most criminals try to avoid generating direct evidence. Hence the prosecution usually must resort to circumstantial evidence to prove the mens rea levels of "purposely" or "knowingly." The same goes for tortfeasors in tort law, if one needs to prove a high level of mens rea to obtain punitive damages.
One example of circumstantial evidence is the behavior of a person around the time of an alleged offense. If someone was charged with theft of money and was then seen in a shopping spree purchasing expensive items, the shopping spree might be circumstantial evidence of the individual's guilt.

[edit]Forensic evidence

Other examples of circumstantial evidence are fingerprintblood analysis or DNA analysis of the evidence found at the scene of a crime. These types of evidence may strongly point to a certain conclusion when taken into consideration with other facts, but if not directly witnessed by someone when the crime was committed, they are still considered to be circumstantial in nature. However, when proved byexpert witnesses, they are usually sufficient to decide a case especially in the absence of any direct evidence. Owing to the development in forensic methods, old undecided cases (or cold cases) are frequently resolved.

[edit]Validity of circumstantial evidence

A popular misconception is that circumstantial evidence is less valid or less important than direct evidence.[citation needed] This is only partly true: direct evidence is popularly, but mistakenly, considered more powerful. Many successful criminal prosecutions rely largely or entirely on circumstantial evidence, and civil charges are frequently based on circumstantial or indirect evidence. Much of the evidence against convicted American bomber Timothy McVeigh was circumstantial, for example. Speaking about McVeigh's trial, University of Michigan law professor Robert Precht said, "Circumstantial evidence can be, and often is much more powerful than direct evidence". [2]The 2004 murder trial of Scott Peterson was another high-profile conviction based heavily on circumstantial evidence.
Indeed, the common metaphor for the strongest possible evidence in any case—the "smoking gun"—is an example of proof based on circumstantial evidence. Similarly, fingerprint evidence, videotapes, sound recordings, photographs, and many other examples of physical evidence that support the drawing of an inference, i.e., circumstantial evidence, are considered very strong possible evidence.
In practice, circumstantial evidence can have an advantage over direct evidence in that it can come from multiple sources that check and reinforce each other.[3] Eyewitness testimony can be inaccurate at times,[4] and many persons have been convicted on the basis of perjured or otherwise mistaken testimony.[5] Thus strong circumstantial evidence can be a more reliable basis on which to determine a verdict. Circumstantial evidence normally requires a witness, such as the police officer who found the evidence, or an expert who examined it, to lay the foundation for its admission. This witness, sometimes known as the sponsor or the authenticating witness, is giving direct (eye-witness) testimony, and could present credibility problems in the same way that any eye witness does.
However, there is sometimes more than one logical conclusion inferable from the same set of circumstances. In cases where one conclusion implies a defendant's guilt and another his innocence, the "benefit of the doubt" principle would apply. Indeed, if the circumstantial evidence suggests a possibility of innocence, the prosecution has the burden of disproving that possibility.[6]

[edit]See also


    Sunday, March 24, 2013

    科學家被捕 李文和事件翻版





    記者李榮 洛斯阿圖報導
    March 21, 2013 09:55 AM 
    胡芷民也曾被調查局問話,雖未有任何對美國不忠的證據,卻仍被太空總署解雇。(本報資料照片,記者李榮/攝影)

    胡芷民也曾被调查局问话,虽未有任何对美国不忠的证据,却仍被太空总署解雇。(本报资料照片,记者李荣/摄影)

    国家太空总署(NASA)中国籍科学家姜波(Bo Jiang)被联邦调查局(FBI)逮捕,不少关注此事的华人认为此事可能是「李文和事件」的翻版。

    30多年前曾在国家太空总署服务,后来被联邦调查局调查的胡芷民20日表示,身为华人承受了很多不公平,「当时他们(指FBI与NASA )非常无理,迫不急待把我fire掉。」
    胡芷民自台大物理系毕业后,至马里兰大学(UMD)攻读博士,经两年博士后训练,进入奇异(GE)公司,研究核能发电。1982年,他转到太空总署,职称为「资深工程师─科学家」,但五个月后即被调查局找上,虽未找到任何他对美国不忠的证据,他仍被太空总署解雇。
    胡芷民回忆,调查局称他的一位从事进出口生意的陈姓友人「可能」是中国间谍,并怀疑胡芷民也涉嫌。胡芷民称他与该友人并不熟识,不清楚详情,愿意接受调查局测谎,却仍被解雇。

    李文和事件发生后,包括圣荷西信使报、ABC新闻等主流媒体都有回顾报导胡芷民的遭遇。「影响太大了,找工作都很困难。」胡芷民说,那时莫名被太空总署解雇,他担心其他科技公司不敢用他,最后只得隐瞒太空总署的经历。当时的太太还认为他「交友不慎」,家庭失和。

    他说,无论是他的博士论文,还是后来在太空总署的工作,都属非机密性的研究。调查局却曾问他是否将博士论文交给该陈姓友人。「我的论文早就在学术期刊Journal of Chemical Physics发表过,哪裡是什麽机密?」

    对于这次姜波被捕,胡芷民认为华裔在美国仍有可能被歧视,但中国籍的姜波能在太空总署接触机密研究也是「不可思议」。他说,理论上敏感的机密研究应该都是美国籍才能接触,而且需经过半年以上的背景查核,就连美国籍的他进太空总署时也无法碰触机密领域,他不解太空总署这次的审查程序。





    Read more: 世界新聞網- 胡芷民:華人在美 承受很多不公
    ======================


    登機前攔截 中國科學家遭FBI逮捕
    編譯中心綜合維吉尼亞州諾福克18日電
    March 19, 2013 06:30 AM | 107330 次 | 
    江波(取材自美國之音網站)
    江波(取材自美國之音網站)
    曾簽約為國家航空暨太空總署(NASA)蘭利研究中心(Langley Research Center)工作的中國籍科學家江波(譯音,Bo Jiang),16日持單程機票在杜勒斯國際機場登上前往北京航班時,遭聯邦調查局(FBI)探員攔截逮捕,因為他攜帶的一台手提電腦,隱瞞未報,向聯邦探員說謊。
    江波18日在維吉尼亞州諾福克聯邦法院過堂,目前未悉他是否聘了律師。FBI將調查他是否涉及陰謀及嚴重違反武器出口管制法。「美國之音」18日報導,據法庭文件顯示,被捕的江波為中國公民,生於1981年11月27日,成都人,居住在華盛頓近郊的維吉尼亞州諾福克市(Norfolk),身高1米65,體重140磅,曾以合同制形式受雇於美國航太總署設在華盛頓近郊的蘭利研究中心。
    據職業社交網站Linkedin上的個人資料顯示,江波曾是國家航空研究院(National Institute of Aerospace)的研究員,曾就讀於中國電子科技大學和美國維州的老多明米昂(Old Dominion University)大學。
    早就盯上江波的國會眾院撥款委員會小組主席渥夫(Frank Wolf,共和黨、維吉尼亞州),18日在記者會上高調宣布此事,他上周首次在聽證會上公開提到江波的名字,並指稱,江波2012年返回中國即攜帶一台屬於NASA的手提電腦,帶走「大量NASA機密文件」。渥夫眾議員的小組對NASA的預算擁有監督權。
    FBI探員15日獲悉,江波突然買了單程機票要在16日離開美國,前往北京,隨即在杜勒斯國際機場於他登機時予以攔截,並進行搜查。國內安全部探員不經意地問他,隨身帶了什麼電子裝置,他答稱有手機、記憶卡、外接硬碟及一台新電腦,但搜查時發現,還有他沒有透露的一台額外手提電腦、一個老硬碟,以及一個SIM卡。
    渥夫說,NASA的蘭利研究中心進行無人空中載具研究及其他具有商用價值和軍事用途的研究,中國可能十分有興趣。他並表示,他接獲的情報指出,目前至少有數十名中國人在類似合約聘雇安排下於蘭利研究中心工作,他們都不是美國公民,許多人甚至沒有綠卡。他說:「要感謝NASA有人檢舉,讓我注意此事,才促成這項調查。」
    渥夫說,逮捕令上還提到FBI知道江波以前曾攜帶屬於美國航太總署的工作電腦回過中國,他們相信這台電腦裡含有敏感信息。他說讓江波接觸到敏感資料,已違反撥款法案中限制NASA與中國太空項目或中國公司合作的條款。
    他在18日的記者招待會上重申自己擔憂,這些信息可能與江波在NASA工作的高科技鏡像技術的有關,「這些信息對中國人民解放軍來說會有及其重要的軍事意義」。
    渥夫表示,江波要帶回中國的硬碟裡究竟包含哪些信息,還要等FBI公布檢查結果後才能得知。NASA究竟有多少外籍雇工?NASA的內部安全系統是否完善?他表示,國會眾院20日將召開聽證,仔細詢問出席作證的航太總署官員。


    Read more: 世界新聞網-北美華文新聞、華商資訊 - 登機前攔截 NASA中國科學家遭FBI逮捕 


    Thursday, March 14, 2013

    在无辜美国公民的车上安装GPS是非法行为

    最高法院对此已有判例,美国各大媒体也有报道,在无辜美国公民的车上安装GPS是一种非法行为。在我这个博客上也转帖了华尔街日报的有关报道。(怎么找不到当时的转帖了? 现在再转帖一次,见下)

    昨天下午(2013-3-13, 5PM 左右),我和周芷云去一位朋友家,他们在 2013-3-11 离美回中国之前,托我们有空时去他们家取信和照看。我们把车停在他们家(302 Brazos St, Gilroy ca 95020)的车道上,进入后院不久,就听到邻居(312 Brazos St, Gilroy CA 95020)后院只隔一道薄薄的木头篱笆紧贴我们站立处,突然发出一阵哗啦啦的声音(似乎是接到命令后有意突然大声拖拉大垃圾桶惊吓我们)只有两秒钟就停了。我吓一跳,问周芷云这是什么声音?她说是隔壁发出的声音。

    这个事情很容易验证,问一下这位邻居,在这个时间是不是有人打电话给你,要求你这么做的? 是什么人打的电话?是警察局,还是如Neighborhood Watch的由警察局辅导的民间组织?具体是怎么说的?

    这类事情太多太频繁地发生在'我身边,其目的是要强烈地提醒我,"不管你走到哪里,你都受到严密的监视。" 也同样强烈地告诉我周围的人,"注意!一个危险分子跑到你身边来了。"

    这么做的指导思想和行为本身都是明显的违法。我 speak out 不仅是保卫我的宪法权利,更是对这个伟大国家的贡献,这是我的国家我的家园。

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    http://online.wsj.com/article/SB10001424052970203806504577178811800873358.html 

    Justices Rein In Police on GPS Trackers

    WASHINGTON—The Supreme Court ruled Monday that police violated the Constitution when 
    they attached a Global Positioning System tracker to a suspect's vehicle without a valid search 
    warrant, voting unanimously in one of the first major cases to test privacy rights in the digital era.

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    不仅非法地安装GPS在我的每一部汽车上,随时监视我车的行踪,还在我家里安装录像头camera
    和窃听器,随时监视我在家里的言行,甚至我人在外面行走没有开车,他们仍然可以很快
    知道我的位置, 立即派人或派车出现在我面前。这种做法已经延续10年以上,法庭不可能
    批准这么长时间的搜索令(valid search warrant).

    汽车尾随跟到家

    很久没有这样了。最近几天,连续发生有汽车在我开车从外面回来时尾随在后,从 Mantelli Dr 右转到 Lions Creek Dr, 再右转到 Heritage Way,最后左转进入我家车库,一直有车紧跟在后,造成我心里一阵阵发紧。

    今天上午(2013-3-13, Wednesday)我去 OSH(Orchar Supply Hardware)买用于修复草地浇水管的配件回来时(上午10:30左右),后面有两部车就这样一直尾随跟到家。

    这种心里发紧的感觉让我一天都不舒服,晚上也睡不好。现在的时间是2013-3-14 凌晨 3点,大概是 1点多醒了,平常打打太极拳,上一下网就可以再睡。今天不行,希望写了这些之后,可以入睡。