Skip to 0 minutes and 5 secondsWe began by introducing you to forensic science through the medium of a case study, and we will end it by reviewing how each chapter showed how science contributed to the development of the investigation. As we do this, remember that the case is based on real events, but the narrative has been adapted to provide a better introduction to forensic science. For example, there was no drugs connection in the original. Remember, too, that the content is not intended to cover everything and that it is at an introductory level. For an example, there is nothing on document examination, hair and fibres, paint, glass, or toxicology. And the whole question of statistical evaluation of evidence has been sidestepped in favour of a logical narrative.

Skip to 0 minutes and 54 secondsThe narrative sets the scene. The facts are that two people have been shot, one fatally, mid-afternoon in August on a road that is quiet in the sense that it is a private access way that ends at Ross Priory on the banks of Loch Lomond. It is not truly quiet since Ross Priory has a bar and restaurant accommodation and access to a members-only boat storage and slip, the jetty. Let's create a list in the form of a table with two columns, one for the real evidence and one for the testimonial or eyewitness evidence. The first row might look like this. Take a few minutes to review the case information from week one and complete the table.

Skip to 1 minute and 38 secondsWhere the two types of evidence corroborate, place them in the same row. The table has limited data on which to formulate a starting hypothesis, and therefore considerable rigour is required to assemble facts and challenge their interpretation. Where to begin. Well, we have been consistent in the view that real evidence trumps eyewitness or other testimonial evidence. So now make a second table, this time with three columns headed Real Evidence, six Ws, and Comment. Complete the Real Evidence column first with the entries in descending order of how important you think that they are, and complete the six W column with what you think they contribute to reconstruction of events. Use the Comment column for notes on the entries and order.

Skip to 2 minutes and 30 secondsThe partially-completed table shown in the illustration has three entries ordered by the reliability of the conclusions based on the evidence. Your table may be different, which is OK. Try not to leap ahead here. There is information in the later weeks that has a bearing on the order of the entries in the first column, and therefore possibly modified hypotheses that are better explanation in the light of all the available data at the time. Now, write down your initial hypothesis and how you will test it. The graphic shows what the table might look like. The most reasonable starting hypothesis, on the basis of the information presented in week one, is the one consistent with Mr.

Skip to 3 minutes and 13 secondsWard's account and the one that was made in the real case. Mr. And Mrs. Ward had both been shot. Mrs. Ward's jewels and purse are missing. At least one of the shots was fired in the car. There is no sign of a gun. This has been a daring holdup and violent robbery conducted in broad daylight and with the assailant thief making a clean getaway. The only significant entry in the Comment column at this point might be that Mrs. Ward was fatally wounded with a shot to the right temple. Remember, this is in the UK, and it is a right-hand drive car, which raises two questions. Why the right side and not the left?

Skip to 3 minutes and 57 secondsAnd why was she shot in the head when Mr. Ward was shot in the arm? There is nothing at this point that excludes Mr. Ward's account, but the real evidence, the nature and location of the injuries, is a challenge to the testimonial evidence, Mr. Ward's account. Repeat the exercise with the table listing the real evidence and testimonial evidence from week two that you think is important.

Skip to 4 minutes and 29 secondsNow repeat the exercise with the second table, but include everything that you think is evidence in the first column, being sure to incorporate the information from the case narrative in week one and two in the Comment column. Label each entry in the Evidence column as real or testimonial and as exclusionary or corroborative.

Skip to 4 minutes and 56 secondsIf you think that the starting hypothesis is still the best explanation, describe why, and comment on any of the evidence presented in week two that appears to challenge your starting hypothesis. If you feel that a revised hypothesis is required, write down the revision and justify the changes. Avoid "I feel." The justification must be based on objective information, but at this point, it need not be restricted to something obtained from real evidence. Some of the points that you should have covered are, the finding of the second cartridge case in the car, the fact that there are clear finger marks in the car that are not from the Wards, and the questions arising from Mr. Dougan giving a false address.

Skip to 5 minutes and 45 secondsReflect that the video in week one illustrates the events as described by Mr. Ward, and may not be what took place. Create the two tables using the material from the case narrative in week three. Review your current hypothesis in the light of the information. Any changes? If not, why not?

Skip to 6 minutes and 12 secondsIt was at approximately this point in the real case that the suspicion that was growing because of the curiosity of the fatal wound to Mrs. Ward began to grow to a serious doubt in the minds of the police. Once Mr. Ward changed his story to one that was a little, but only a little, more credible regarding the location of the gunman when the shots were fired, their whole focus changed. The evidence of the gunshot residues. Why would he have these on his sleeve if events had been as he has described? And the location of the two points of impact of the bullets were as close as was needed to exclude his version of events in the minds of the investigators.

Skip to 6 minutes and 49 secondsThings are not quite cut and dried yet. Where are Mrs. Ward's jewels? Where is the gun? And if Mr. Ward wanted to kill his wife for whatever reason, why risk doing it in broad daylight in a fairly public place? Many of you will have seen or at least heard of one or more of several experiments describing the impact of stressful surroundings on the accuracy of the recollection of events by persons involved. Being the victim of a armed robbery in which your spouse is shot and killed must be high in the ranks of stressful experiences. There is some information in the resource material that might be interesting to read in relation to this.

Skip to 7 minutes and 27 secondsDid your tables from week two include the information from the witness about the Ward's car driving off down the road to the lochside rather than to the exit from the priory? Perhaps not. It may not have seemed important at that point. However, to move from the not very realistic version of the shooting as given by Mr. Ward being due to his distressed state, to it being because he was lying needs some more evidence, perhaps the finding of Mrs. Ward's possessions or the gun. And of course, his omission of the detour to the lochside added to the suspicions of the investigators.

Skip to 8 minutes and 4 secondsThe tyre impression evidence was more than enough to convince the SIO and DI Morrison that the car had been near the jetty. And despite the lack of detail, they were also confident that the partial footwear mark placed Mr. Ward outside of the car. Driving down to the relative privacy of the lochside, shooting Mrs. Ward, and then what was meant to be a minor injury to himself and throwing the gun into the water became the investigators' confident interpretation of the incident, with ample corroborative evidence and nothing to exclude it. Is it yours? Before responding yes, the points about stress and recollection are still valid.

Skip to 8 minutes and 44 secondsThe lochside may have been quieter than the road, but it is still an improbable time and place to commit a murder, and there was nothing to link the gun with Mr. Ward. When entering the data in your tables, differentiate what is relevant to the murder and what applies to the drugs lab. The technical investigation of the scene at the cottage resulted in inceptive evidence. Unlike the range of possible explanations for the evidence in the murder inquiry, there is little scope for alternatives. The chemistry is definitive, and the results prove this was a drugs lab scene.

Skip to 9 minutes and 22 secondsThis is typical of inceptive evidence, which is usually quite specific and clear as to what happened, but provides little or no insight into who was involved. The statement from Miss Anderson, which is subjective testimonial evidence, was the missing piece providing the police with a motive. The discovery by the investigators of a mistress in the real case was likewise the element that wrapped things up. There are two loose ends for you to consider. Was it coincidence that Mr. Dougan was, or appeared to be, first on the scene? Where are Mrs. Ward's jewels? And related to this, what is the evidence to link the gun with Mr. Ward? Could it not be that the real gunman was not Mr.

Skip to 10 minutes and 9 secondsWard, that he did not mean to commit murder and got rid of the gun by throwing into the loch? These missing links and the reliability of the BPA reconstruction were the focus of the defence challenges to the forensic science evidence in the real case. The case has unfolded as a narrative device to explore and illustrate the principles of forensic science. We dealt with five areas, the first of which was the crime scene because of its overwhelming significance to any forensic investigation. Miss, contaminate, or wrongly interpret evidence at the scene, and there is no recovery.

Skip to 10 minutes and 48 secondsThe other four that we chose were fingerprints, firearms, DNA, and drugs, sometimes referred to as the four D's of forensics, dactyloscopy, derringers, DNA, and drugs because they constitute the bulk of the workload of a modern forensic science laboratory and cover the spectrum of forensic investigations from simple visual comparisons to those requiring advanced technology. All of them can be difficult to translate into terms that will be readily understood by a lead juror. Sometimes the jargon will confuse and conceal. In others, it will create an aura of certainty in what the witness has to say that is, perhaps, rather more than is wanted.

Skip to 11 minutes and 32 secondsIn real life, our case ends with a lengthy written report and an extensive and detailed examination and cross examination of the methods used and conclusions drawn. But in a way, these are only vehicles to convey the content of the investigation, and one of the tools introduced in week one can do this much more simply. Your final task is therefore to review the tables you have created in this last module and write your own reports based on the questions in the six Ws and the answers as you see them.

The case study - Putting the pieces together

Of course, what you really want to do is get to the case study! We are going to do that by working our way through all of the evidence that has been presented in a structured manner.

We have provided copies of the tables referred to in the video in the ‘downloads’ resource section at the bottom of the page, so that you can fill these in as you go and work alongside the video. You may have to stop and start the video to complete this and there are intentional gaps in the narrative to indicate when you should be working on your tables.

Some of you may approach this with “what’s the point - it’s obvious from the start that Mr Ward killed his wife and faked a robbery to conceal it”. Well, you may be correct, but what if you are wrong? In that case a dangerous killer has got away with murder and may try it again! Or what if it was an accident or suicide? An innocent man will be wrongly incarcerated (or in some jurisdictions, executed). Any death investigation is a serious matter and any forensic investigation must be treated with the utmost rigour that the scientific method can bring to the process.

The introduction to this week mentions the legitimate place for intuition in an investigation, but intuition is only another tool to tease out the facts and shouldn’t be used as a short cut to an answer. Remember what you have read in the short paper on the History and Philosophy of Science and the place that Peirce occupies. We have also added some information in the ‘downloads’ resource section at the bottom of the page relating to the the reliability of eyewitness testimony referred to in the video.

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This video is from the free online course:

Introduction to Forensic Science

University of Strathclyde