>What is the percentage of cases solved using forensic techniques? A: I don't have a number, but usually forensics is an *adjunct* to plain old detective work. For example, in my case, I don't go out and bust drug dealers; all I do is analyze their wares. If the case goes to court, all of the observations and actions by the patrol officers and the narcotics detectives (what they did and why they did it) has to be related to the jury, and comes under scrutiny by the defense lawyers. There has to be "probable cause" for the arrest. Custody of the evidence has to be controlled and documented, to insure that it wasn't contaminated or tampered with prior to its arrival in the lab. My analysis of the evidence is just the end of the whole process - and if the analysis shows that there were no drugs present after all (the guy was selling sugar instead of meth, maybe), then the whole case collapses and the charges are dismissed. If drugs were actually present, the defendant may decide to plead guilty and not go to trial. Even if there is a trial, if the defense counsel is able to show there was a break in the chain of custody of the evidence (such that the evidence I analyzed might *possibly* not be the same evidence that was seized from the defendant at his arrest) or that there was not legal probable cause to justify the arrest, then the case ends. If all the other requirements are met, then the prosecutor still has to show that I'm qualified as a drug analysis expert (this is done based on my educational background and experience) before I can testify about how I analyzed the evidence and what the results of my analyses were. My analysis is like the final piece in the puzzle. In cases of rape or murder, forensic analysis can become the linchpin to the entire case. There have been a few cases where a person was convicted based on old (pre-DNA) serological techniques, and subsequent re-analysis using modern DNA techniques actually *exonerates* the person. There are also some cases that have been solved via CODIS (Combined DNA Indexing System - a national DNA database) matches, where traditional investigative/detective techniques have run into a dead end. Usually though, forensics provides the "nail in the coffin" that provides the conclusions formed during the preceding detective work with some scientific certainty. 大约有百分之几的案件是靠监识科技来破案的？ 我没有一个确切的数字，不过监识通常是警探工作的附属品。就我的例子来说， 我并不到外面去抓毒枭，我只分析他们的器械。上了法庭之後，巡警以及缉 毒组探员所做的观察还有行动〈做了什麽/为什麽这麽做〉都必须呈交给陪审团。 而这些观察和行动都会被辩方律师一丝不苟的彻底检查。逮捕必须是有正当理由 的，证物的监护权有受到管制且记录，以保证在到达实验室之前没有被污染或是 动过手脚。我的分析只是整个执法过程的最後一个步骤，如果分析结果显示证物 里其实并没有毒品，〈也许被告卖的是糖而不是脱氧麻黄硷〉整个案子就终结了 ，而检方也必须放弃告诉。 如果我们证实毒品的存在，被告可以选择认罪，这时就不需审判。而如果在审判 的过程中，辩方律师可以证明处理证物的过程有瑕疵〈譬如说我分析的证物有可 能并不是在被告被逮捕时所扣留的那份〉，或是警方没有正当理由去逮捕被告， 这个案子也会被终结。 就算以上的条件都被达到了，在检方证明我是个有分析资格的毒品分析专家之前 〈这是建筑在我的教育背景还有分析经验上〉，我都不能我为分析的证物还有得到 的结果作证。我的分析就像是拼图的最後一块一样。 在强暴或是谋杀一类的案件中，监识工作可能扮演决定性的关键。曾经有案件是 靠血清学〈没有DNA前所用的技巧〉来判定被告有罪，但在重新使用现代DNA分析 後而还给被告清白的。 还有一些本来当地警方使用传统技巧，却追进死胡同的案子，是靠着CODIS 〈全国DNA资料库〉来破案的。 通常监识科学可以提供检调工作一定程度上的科学保证，是拍板定案的阖棺钉。 >Do all cases require CSIs? A: No, definitely not. Nowadays most drug cases as well as sexual assault cases will make use of forensic analysis. Murder cases can often make use of forensics, for trace analysis and/or firearms analysis, and possibly for DNA analysis. Driving while intoxicated cases depend on analysis for alcohol or drugs. Burglary cases *may* use forensics (for example to match the tools used to break in, with the marks they left behind at the crime scene, or DNA traces). But many other cases, such as domestic violence, simple assault, fraud, robbery, speeding tickets, streaking (just kidding - are you still paying attention?) - don't usually involve CSI types. 所有的案件都需要CSI吗？ 不，绝对不是这样。现今大部分毒品以及性侵害案件都会用到监识分析。谋杀案 通常也会使用监识科学来做微量证物/枪械，又或者是DNA分析。酒後/吸毒後驾车 也需要酒精/毒品浓度分析。 抢劫案件可能会用到监识工作〈如用工具留下来的痕迹来证明使用的工具，又或者 是DNA证据〉。但在大部分的情况下，如家庭暴力、一般侵犯罪、诈欺、抢劫、超速 、露鸟〈开玩笑的，你还在听吗？〉，通常是不用CSI出动的。 --

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