Crime Scene Training

Interview and Interrogation Part 2

PART 2

The first step law enforcement officers should take is to ensure that they understand and take advantage of the procedural differences that are required when a suspect invokes the right to silence as opposed to invoking the right to counsel. Because there is a significant difference between the procedural protections offered to a suspect who invokes the right to counsel and one who merely expresses a desire to remain silent, law enforcement officers should be certain they know which right a suspect is invoking.

If, following the advice of rights, the suspect’s response leads officers to believe that the suspect is invoking his rights, but the officers are unsure of which right is being invoked, the officers could conceivably follow up by asking the suspect if he is, in fact, invoking the right to silence. If a suspect gives an affirmative response, then officers should immediately stop questioning. However, since only the right to silence has been invoked, a second attempt to obtain a waiver may be made after waiting a reasonable period of time. 

Similarly, when a suspect is being read his rights for the first time, it may be best to avoid encouraging a blanket invocation of rights that could occur if the entire list of rights is given before inquiring whether the suspect wishes to waive or invoke any or all of them. There is nothing in the rule to preclude the suspect being told first that he has the right to remain silent and then asked whether he wishes to waive that right. 

If the suspect indicates a desire to waive the right to silence, then he should be advised of the remainder of his rights and asked whether he wishes to waive those rights as well. If, on the other hand, the suspect is first advised of the right to remain silent and chooses to invoke that right, then no further advice of rights need be given at that time and the interrogation should cease. 

However, a subsequent attempt to interview a suspect could be made after waiting a reasonable period of time, since only the right to silence was invoked. By refraining from advising a suspect of the right to counsel until the right to silence has been waived, the law enforcement officer may reduce the possibility that the rule in Minnick will be triggered. 

Continued in Part 3  --  Coming Soon

Microbes and Dead Mice

Microbes and Dead Mice--The Basic Ingredients of a Microbial Clock

By: Don Penven

Jessica Metcalf, a Colorado University postdoctoral researcher puts forth the interesting hypothesis that the estimated 100 trillion (give or take a few billion) microbes that live on every human being are similar to microbial clocks on human corpses.

Metcalf says that establishing time of death is a crucial piece of information for investigators… but existing techniques are not always reliable. "Our results ( from a now-completed study) provide a detailed understanding of the bacterial changes that occur as mouse corpses decompose, and we believe this method has the potential to be a complementary forensic tool for estimating time of death."   

Death scene investigators use a variety of tools and methods to estimate time of death at crime scenes including corpse temperatures, grave soil analysis, insect infestations, and the time stamp on the subject’s cellphone. But the accuracy of any contemporary methods are influenced by the lapse of time from death to discovery and examination.

Metcalf and her associates developed gene sequencing techniques on both bacterial and what she describes as microbial eukaryotic organisms including fungi, nematodes and amoeba on mice, and they were able to pinpoint the time of death after a 48-day period to within roughly four days. Even more accurate results were seen following a 34-day analysis with the time of death estimate being within three days, Metcalf said.

The documented research resulted in a paper on the subject that was published Sept. 23 in the new online science and biomedical journal, eLIFE, a joint initiative of the Howard Hughes Medical Institute, the Max Planck Society and the Wellcome Trust Fund. The study was funded by the National Institutes of Justice.

David Carter, co-author of the study said that the researchers tracked microbial changes on the heads, torsos, body cavities and associated grave soil of 40 mice at eight different time points over the 48-day study. “The stages after death include the ‘fresh’ stage before decomposition, followed by ‘active decay’ that includes bloating and subsequent body cavity rupture, followed by ‘advanced decay,’” Carter said.

Part of the project included the charting of "blooms" of common soil-dwelling nematodes well known for consuming bacterial biomass that occurs at roughly the same time on individual mice during the decay period. "The nematodes seem to be responding to increases in bacterial biomass during the early decomposition process, an interesting finding from a community ecology standpoint," said Metcalf.

"This work shows that your microbiome is not just important while you're alive," said CU-Boulder Associate Professor Rob Knight, the corresponding study author who runs the lab where the experiments took place. "It might also be important after you're dead."

"There is no single forensic tool that is useful in all scenarios, as all have some degree of uncertainty," said Metcalf. "But given our results and our experience with microbiomes, there is reason to believe we can get past some of this uncertainty and look toward this technique as a complementary method to better estimate time of death in humans."

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Interview vs. Interrogation -- Part 1

By: Don Penven , "A Tangled Web"

Introduction

A polygraph (often referred to as a Lie Detector) is an instrument that measures and records several physiological responses such as blood pressure, pulse, respiration and skin conductivity while the subject is asked and answers a series of questions, on the theory that false answers will produce distinctive measurements. The polygraph measures physiological changes caused by the sympathetic nervous system during questioning.

Within the U.S. federal government, a polygraph examination is also referred to as a psychophysiological detection of deception (PDD) examination. Several other technologies are also used in the field of lie detection, but the polygraph is the most famous. An example of a different method that is commonly used is a device that monitors the response of the individual’s eye. If the iris contracts suddenly, this could indicate that the person is lying. Another device also in use is the Voice Stress Analyzer, which electronically measures tremblors in a person’s speech.

Polygraphs are often used as an interrogation tool with criminal suspects or candidates for sensitive public or private sector employment. The use and effectiveness of the polygraph is controversial with the manner of its use and its validity subject to increasing criticism. Most, if not all, U.S. courts have ruled against its admissibility as evidence.

Interview and Interrogation

Many thousands if interviews and interrogations take place every day. First it is important to draw distinctions between the two. An interview consists of a conversation, generally between two persons, regarding specific topics such as:

1. A job interview

2. A salary/performance review

3. A traffic accident

4. A crime such as burglary, robbery, homicide, rape, etc.

Interview: Think of an interview as a conversation between law enforcement or security officer and a subject. An interview may be with a witness, victim or others thought to have information about an incident. Many interviews may evolve into an interrogation.

Interrogation: An interrogation begins when the investigator gains certain knowledge about the incident and/or subject that causes him to suspect that the subject may be in some way involved in the incident. There are basically two approaches to conducting an interrogation:

1. Accusatory or confrontational: In this kind of interrogation the subject is accused of having committed the crime right up front, and he is expected to deny the accusation or confess to it. In most cases on record, he will invariably deny it, and for this reason many skilled investigators use the alternative approach.

2. Non-accusatory or non-confrontational: This method is now being widely taught and it enjoys wide acceptance in the law enforcement community for the simple reason that it produces the best results. Here’s how each format works:

Confrontational: Usually following a brief introduction by the investigator, the subject is then accused of having committed the crime. Approaches used include, but are not limited to, “We have reliable information that you held up the liquor store on Grant St. two nights ago, and now we want to hear your side of the story.”

Another approach is: “We’ve talked with your friend, John and he told us the whole story. We want to give you a chance to tell your side of it.”

And of course there’s the “Good Cop – Bad Cop” routine when two officers, one Officer Friendly and the other Officer Nasty, go back and forth trying to get the subject to side with Officer Friendly and confess. This technique is so old and shop-worn that few felons will fall for it. After all, many crooks watch the “Law and Order” reruns. Some consider this tactic as the Lennie Briscoe approach. The Accusatory/confrontational approach is still used every day even though it seldom produces positive results. So why use it?

Non-confrontational: This approach will take a little more time because the investigator is seeking to establish a rapport with the subject. Once the subject begins to relax somewhat, he is told that the investigator believes that the subject MAY have knowledge of a particular incident/crime—not that he is suspected of having committed it. Throughout this text we will refer to the non-confrontational approach and will provide several examples as to how to employ it.

Miranda: Miranda v. Arizona was a landmark 5-4 decision of the U.S/\. Supreme Court, which was argued February 28—March 1, 1966 and decided June 13, 1966 The Court held that both inculpatory and exculpatory statements made in response to interrogation by a defendant in police custody will be admissible at trial only if the prosecution can show that the defendant was informed of the right to consult with an attorney before and during questioning and of the right against self-incrimination prior to questioning by police, and that the defendant not only understood these rights, but voluntarily waived them.

The U.S. Supreme Court’s decision:

Chief Justice Earl Warren, a former prosecutor, delivered the opinion of the Court, ruling that due to the coercive nature of custodial interrogation by police (Warren cited several police training manuals which had not been provided in the arguments), no confession could be admissible under the Fifth Amendment self-incrimination clause and Sixth Amendment right to an attorney unless a suspect

had been made aware of his rights and the suspect had then waived them. Thus, Miranda’s conviction was overturned.

The person in custody must, prior to interrogation, be clearly informed that he has the right to remain silent, and that anything he says will be used against him in court; he must be clearly informed that he has the right to consult with a lawyer and to have the lawyer with him during interrogation, and that, if he is indigent, a lawyer will be appointed to represent him.The Court also made clear what had to happen if the suspect chose to exercise his rights:

If the individual indicates in any manner, at any time prior to or during questioning, that he wishes to remain silent, the interrogation must cease … If the individual states that he wants an attorney, the interrogation must cease until an attorney is present. At that time, the individual must have an opportunity to confer with the attorney and to have him present during any subsequent questioning. 

In essence, what all this means is that when an interview turns into an interrogation, the Miranda warnings must be given. In study after study, however, it may startle you to know that the majority of subjects waive the Miranda rights and offer to give a voluntary statement. They will even sign a waiver to that effect. This, of course, doesn’t prevent them from invoking those rights later on.

So why do people waive these rights? The best answer found in countless studies is that the individual wants you to believe he has nothing to fear. He wants you to believe in his innocence.

Continued in Interview and Interrogation--Part 2

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