Chain of Evidence in a Fire Investigation - Assignment Example

Assignment briefing Name: Date: University Affiliation Assignment briefing 1. With reference to the fire investigation books explain the distinction between a smoke horizon and a heat horizon. And explain how the two horizons could be evaluated. What could interfere with the horizon and would be a help or hindrance to the investigation. a. Smoke horizon This refers to the upper most layer of smoke that is made by a low lying level of inversion of temperature. This makes it appear as a horizon layer which can be observed as one looks as one see it from a point on earth against the sky. In such occurring cases the real horizon layer has been covered by the layer of smoke. (Bryan, J. 1995). Figure 1: image of a smoke horizon During smoke evaluation it involves several studies which are done together to achieve the same goal more effectively. They include: air quality monitoring where special device is used to determine the amount of particulate matter that is present in the air at that given time or period. The results are useful in determining the extent to which the air quality has changed in the atmosphere of measurement. Compliance law monitoring: this is very useful when it comes to determining the nature and extent to which the public space is being polluted by the smoke. Some of the questions being asked in this process are the laws set in place being effectively implemented. the economic impact of the smoke on the society is also assed how many smoke generating business are there in the society the level of employment such sources do generate alongside the income so that one can be able to know the negative impacts versus the benefits brought along. (Bryan, J. 1995). Heat horizon Heat horizon refers to a layer of heated air that feels the low level caused by extreme air heating raising its temperatures. It brings about a horizon of heated air when observed from a distance against the sky. This covers the actual horizon making it to appear to be having heat waves reflection. (Bryan, J. 1995). Figure 2: image of a heat horizon During evaluation of a heat horizon there are several methods which can b used one is by use of mathematical temperature models to determine the extent of heat in the atmosphere. Where Tap refers to the apparent temperature, Tair refers to the air temperature and Tdewpt refers to the dew point temperatures located at a distance of 2 meters in degrees Celsius During the simulation the selection of temperature was obtained by dividing it through an equal range of intervals which ensured equity was obtained in collection of data so that the most precise and accurate answers can be obtained. (Bryan, J. 1995). The other way is by looking at the impact of increased heat waves on the agricultural out put. Plants require a lot of energy for manufacture of their own food however if in excess the heat destroys the plants hence the output from the agricultural sector will have to be reduced drastically. The other way is by the economic and social impact assessment at very extreme heat the levels of interaction by people is very low due to the uncomfortable heat levels therefore one can be able to easily tell what extent the heat horizon has affected the people. (Bryan, J. 1995). 2. What is a chain of evidence and why is it important in a fire investigation The chain of evidence refers to the basics of establishment of a given cause of fire has been found. This refers to a series of proof which can be used to either proof a case accusation is true or it’s false. There are several things which can be taken to be evidence reliable in any fire investigation scenario. Some of the cases are: any object that is found left at the fire crime scene or has been picked from the crime scene. Anything that in one way or the other is linked to a crime associated with fire. Evidence can also be defined as anything which anyone can take to a trial court and present it for purpose of filing a case Against someone. (Proulx, G. 1995). Chain of evidence is very important in determining the root cause of any fire accidents that is under investigation. There are several types of evidences that one would want to consider during any fire investigation. They are: direct evidence these type brings about proof that is through any of the five human senses. They are sense of smell, sense of sight, sense of taste, sense of sound and sense of smell. For example when one testifies an explosive being dropped into a building and sees the building catch fire. The second type of evidence is indirect evidence: they only help to identify truth about certain elements in a given investigation; they don’t proof anything by their own means. The third type of evidence is the physical/real evidence: such type of proof do not need any explanation at all by looking at what you have at hand you can clearly tell what happened without any doubt. A good example is a bomb expert at a crime scene spotting fuse to a bomb. (Proulx, G. 1995). There are several examples which can be used as evidence examples include, tracks left behind, DNA testing samples, photographs taken during and after the crime scene, recorded documentation. When using or collecting a chain of evidence there are five important things which one will have to keep in mind. One has to gather and poses the evidence in a legal way, the evidence should be well described in notes form, the evidence should be well identified with the crime under investigation, the evidence is the well packaged and kept under safe custody so as no one can interfere with it. When one is preparing a chain of evidence one should be able to have it as brief as possible with the highest level of precision. It should be identified and owned by the founder. Whenever it’s given to someone else it should always be signed for. A chain of evidence is very important in proofing any cause of a fire accident therefore it should be well collected and guarded from any interference. (Proulx, G. 1995). 3. How could it be possible that a room with two apparent sources of ignition could possibly not be the work of an arsonist? If it happens that a fire incident has occurred accidentally then there is someone who is behind the fire cause, this person is referred to as the arsonist where as the act referred to as arson. A motive is the main reason behind such an activity for instance revenge against someone or an organization. Without such motives it cannot be concluded that the fire was caused by arson. (Horasan et al 1994) The fire may have two causes of ignition but in order for it to be considered as an arsonist attack it should also be having something like material or chemical which spread up the fire to burn faster than the ordinary fire scenario. For a successful planned fire incident it usually has the sources which do come from the low ground providing a wider consuming area so in one way or the other a fire may be having more than one source as ignition point but looking at occurrence it has originated from the middle or top of the building such can rarely be considered as an arson attack. (Horasan et al 1994) When also looking at the ignition sources if highly flammable accelerants such as petrol were used and trail marks can be traced then the fire can be concluded to be one that has been planned by people with malicious intentions. On the other hand therefore if a fire case happens to occur with a given number of sources but no trail of accelerator that may have been used in the fire then it can be concluded that such an incident may have occurred accidentally and coincidentally to have more than one source . This is attributed to the fact that if the fire was deliberately put on then the person would want it to have a lot of losses left behind by the flames by ensuring it consumes a large area within a very short time. This is made possible by the use of a burning accelerator. (Horasan et al 1994) 4. The fire investigation text book “scientific investigation of fire investigation” second edition by john letini contains many case studies in which the author has given a second opinion about the origin and cause of fire. Pick any of these cases and write a critic giving emphasis on the examples of errors and poor decision making by the original fire investigators. In the results given by the first investigation team the fire had been caused by arson. According to the team the suspect used gasoline as an accelerator to the fire. The gasoline had been hidden at the back of an old car which was not functional. However looking at the evidence that had been presented by the team it was unanimously decided that the evidence which was used to give the results of the investigation was not correct or worthy proving the judgment made. Several issues had arisen from what was provided as the evidence in this case. (John 2000) The first one was why should one put gasoline jag hidden at the back of an old car which was not functioning. This could have been a careless action taken by the suspect since its obvious if one is planning such an attack one should hide the accelerate he is planning to use in a more safe zone. Simply because when investigating the team would straight away go to any stationary vehicles in the vicinity and one of the first places to be checked would be the boot of the car and that’s where the investigators claimed the jag of gasoline was found. (John 2000) Secondly if the nature of gasoline in the jag resembled the one that was placed in the mower which was operational on the garden the day before the fire incident occurred how comes it wasn’t thought that the jag with gasoline had been kept in the back of the car for future use in the mower since the mower is powered by gasoline and there was no difference in the nature of the two gasoline’s one found in the mower and the one in the jug. This casts more doubt on the credibility of the investigations that had been carried out by the first team. (John 2000) Thirdly the investigators claimed that some portion of gasoline was found left in the jag. This also raises eyebrows simply because if someone had the intention of starting the fire he could have used as much accelerant which was gasoline in this case as possible. On the contrary in this investigation the suspect only decides to use a fraction of what was in the jag and returns the remaining in the back of the car. Any smart person after committing such a crime would go away with the can o containing the gasoline to try and hide any evidence but on the contrary in this scenario the suspect decides to leave it behind. This are some of the examples that provide enough proof the first investigators made very obvious mistakes which should not have been made during investigation of a fire . So many crucial scenarios from any evidence obtained had been ignored hence their findings were nullified beyond any reasonable doubt. (John 2000) REFERENCE 1. Brennan, P. (1997). ‘evaluation of smoke horizon , Proceedings of the Fifth International Symposium, Yuji Hasemi (ed.), World Congress Centre, Melbourne, Australia. 2. Bryan, J. (1995). ‘Behavioral responsein fire investigation ’, SFPE Handbook of Fire Protection and investigation Engineering, 2nd edn. 3. Bryan, J. L. (1983). ‘An Examination and Analysis of the Dynamics of the Human Behavior’, the MGM Grand Hotel Fire, NFPA, Quincy, MA., USA. 4. Fahy, R. & Proulx, G. (1997). ‘smoke and heat horizon evaluation’, Fire investigation Science: Proceedings of the Fifth International Symposium, Yuji Hasemi (ed.), World Congress Centre, Melbourne, Australia 713–24. 5. Horasan, M. & Bruck, D. (1994). ‘Investigation of causes of fire”, 4th International Symposium on Fire Safety and investigation Science Proceedings, ISFPA, Gaithersburg, MD, USA 715–26. 6. john letini (2000) “scientific investigation of fire investigation” second edition, ISFPA by pages 76-79 7. Jones B. K. & Hewitt A. J. (1986). ‘Leadership and Group Formation in High Rise Building Evacuations’, Fire Safety Science: Proceedings of the First International Symposium, Hemisphere Publishing Corp. Washington,DC, USA 513–22. 8. Pauls, J. (1996). ‘Evidence analysis , SFPE Handbook of Fire investigation, 2nd edn, National Fire Protection Association, Quincy, MA.,USA. 9. Proulx, G. (1995). ‘evidence obtaining and evaluation in fire incidents buildings’, Fire Safety Journal, 24 (3), 229–46. Read More

The chain of evidence is very important in determining the root cause of any fire accidents that are under investigation. There are several types of evidence that one would want to consider during any fire investigation. They are direct evidence this type brings about proof that is through any of the five human senses. They are a sense of smell, sense of sight, sense of taste, sense of sound, and sense of smell.  For example when one testifies an explosive being dropped into a building and sees the building catch fire. The second type of evidence is indirect evidence: they only help to identify the truth about certain elements in a given investigation; they don’t prove anything by their own means. The third type of evidence is the physical/real evidence: such type of proof does not need any explanation at all by looking at what you have at hand you can clearly tell what happened without any doubt.  A good example is a bomb expert at a crime scene spotting fuse to a bomb. (Proulx, G. 1995).

 Several examples can be used as evidence examples include tracks left behind, DNA testing samples, photographs taken during and after the crime scene, recorded documentation. When using or collecting a chain of evidence there are five important things that one will have to keep in mind. One has to gather and legally poses the evidence, the evidence should be well described in notes form, the evidence should be well-identified with the crime under investigation, the evidence is well packaged and kept under safe custody so as no one can interfere with it.

When one is preparing a chain of evidence one should be able to have it as brief as possible with the highest level of precision. It should be identified and owned by the founder.  Whenever it’s given to someone else it should always be signed for.  A chain of evidence is very important in proofing any cause of a fire accident therefore it should be well collected and guarded against any interference. (Proulx, G. 1995)

How could it be possible that a room with two apparent sources of ignition could not be the work of an arsonist?

If a fire incident has occurred accidentally then there is someone who is behind the fire cause, this person is referred to as the arsonist whereas the act is referred to as arson. A motive is the main reason behind such activity for instance revenge against someone or an organization. Without such motives, it cannot be concluded that the fire was caused by arson. (Horasan et al 1994)

The fire may have two causes of ignition but for it to be considered as an arsonist attack, it should also be having something like material or chemical which spread up the fire to burn faster than the ordinary fire scenario. For a successfully planned fire incident, it usually has the sources which do come from the low ground providing a wider consuming area so in one way or the other fire may be having more than one source as an ignition point but looking at occurrence it has originated from the middle or top of the building such can rarely be considered as an arson attack. (Horasan et al 1994)

 When also looking at the ignition sources if highly flammable accelerants such as petrol were used and trail marks can be traced then the fire can be concluded to have been planned by people with malicious intentions. On the other hand therefore if a fire case happens to occur with a given number of sources but no trail of accelerator that may have been used in the fire then it can be concluded that such an incident may have occurred accidentally and coincidentally to have more than one source. This is attributed to the fact that if the fire was deliberately put on then the person would want it to have a lot of losses left behind by the flames by ensuring it consumes a large area within a very short time. This is made possible by the use of a burning accelerator. (Horasan et al 1994)

The fire investigation textbook “scientific investigation of fire investigation” second edition by john letting contains many case studies in which the author has given a second opinion about the origin and cause of the fire.

Read More