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Ask Laura

Please post your questions for this week in the comments section below. Laura will select the most liked/interesting questions and publish her response to these on this step by Wednesday of Week 2.

I’d like to extend a very warm welcome to you all, and thank you for joining the Introduction to Forensic Science course. It’s great to see so many people from all across the world taking the course and getting involved with the discussions. Thank you for all of your great questions this week, and for all of the positive comments about how much you are enjoying the course.

It is also fantastic to see you all helping each other and sharing your thoughts and information, for example Heather Barnes comments on character traits in response to Anthony James. (I’d add to this that a Forensic Scientist has to be patient and be able to deal with repetitive tasks that require a long period of focus, this is something we look for when interviewing!). Also, Brian W responding to Kevin Sheen regarding Forensic Scientist’s interviewing suspects – I wholly agree, never in over 12 years have I done this and only once (under exceptional circumstances) have I spoken to a witness – this is the role of the police, NOT the scientist.

I wish that there was the time to answer all of your questions but I’ve focused on those that were most popular this week.

Firstly though I wanted to clarify something that has come up in many of your questions and this is about the role of Forensic Science and the role of the Police. It is the Police who “investigate”, who gather information, collate evidence and try to “build a case”. To do this they may use trained forensic experts, either forensic scientists in a lab or Scene of Crime officers at the scene. These experts are usually working under the direction of the Senior Investigating Officer (SIO) but they operate independently and impartially from the Police. The role of Forensic Science and the Police are separate and not the same, the forensic scientist does not make any comment on the alleged offence and does not offer any thoughts on the guilt/innocence of any suspect. The Forensic Scientist may interpret the forensic findings only and then communicate this to the Police/SIO.

Crime Scenes and Crime Scene Managers

Millie Lloyd asked about Crime Scene Managers. This is particularly well illustrated using the example of the UK, which covers three jurisdictions (and legal systems); England & Wales, Scotland and Northern Ireland. In Scotland, CSMs will usually be police officers, whereas in England & Wales, they will tend to be trained civilians. However, in general, a CSM’s role is a very important one and because of the significance of this role, they receive specialist training and so are more experienced and qualified to make difficult logistic and strategical decisions than other SOCOs.

The CSM uses their training to do an initial assessment of a scene, plan the forensic strategy and agree this with the Senior Investigating Officer. They brief scene personnel and allocate appropriate numbers to individual aspects of scene examination (which will differ depending on the detailed requirements of the case). They are also responsible for managing the welfare of all scene personnel, carrying out health and safety risk assessments and implementing control measures as well as releasing the scene.

Sharron Phillips asked about role of SOCOs when there are multiple scenes. Once the SOCO has finished at the scene, logged in the evidence to the store and completed their scene notes their role is complete (except if they are called to give evidence in court at the end), any further forensic testing done by a scientist at a lab and any subsequent “investigation” is done by the Police until the point at which the Police close the case which may be months or even years later. Generally, SOCOs work on one scene at a time, but they may visit multiple scenes in one shift if they are smaller, or spend several days at the same scene if it is larger/more complex.

Olga I asked about dealing with contamination at a scene. This depends on the type of contamination you mean, there are strict procedures in place for crime scenes to reduce the chance of contamination, but if there are any concerns this should be clearly documented in the SOCOs scene notes. An example is the training of first responders to minimise any effect on the crime scene without compromising the importance of their own role. This varies depending on country and jurisdiction. In many countries, police officer training includes only very basic coverage of forensic science, whereas better scientific training and awareness for police officers and other members of the criminal justice system, such as lawyers and judges, would be extremely valuable. In the UK a prime example of this is fire scenes; apart from damage done by the water which is unavoidable, historically it was common practice for firefighters to remove furniture etc from a property as they extinguish the fire, however this could significantly compromise any forensic evidence. Today, a more collaborative approach using awareness training between the fire brigade and forensic providers has led to a greater understanding from both sides to allow both parties to perform their duties to the best of their abilities with minimal impact; they do not routinely throw out the furniture!

Robert Wallings asked about the steps after the scene has been processed, the Crime scene manage will advise the Senior Investigating Officer on the investigative potential of different evidence types and the value of using any specialists (which will also depend on the detailed requirements of the case), as well as coordinating the individual experts within the overall scene. As you correctly point out, it will take some time to collate all the relevant paperwork such as the pathology results, but any forensic testing may be staged, authorised only if pertinent to the investigation. This testing and can then take anything from days to weeks in the UK and is coordinated by the Police.


Juan Sebastian Cortes Arango, Kerry Lovell, Emma Biggins and Madeline M all asked about evidence, what to do if it is destroyed, how to address a lack of leads/an investigation with little evidence and how to organize evidence so it is safe and secure. Again, many of these are the remit of the Police who are investigating the crime, not the forensic scientist.

In terms of the scene examination, once the CSM is happy that anything of potential forensic value has been seized they will release the scene. The seized evidence is securely sealed and a chain of custody record is used to track its movement between, people and locations, for example, from the crime scene, to the laboratory and to the court. It is each individual person’s responsibility to complete the chain of custody record when they are in possession of the evidence. Within each of these locations there are Standard operating procedures and quality management systems used that document exactly when and how this information should be recorded. It is commonplace in the UK to use a computer based laboratory management system which allows for barcode tracking of evidence types as well as all information pertinent to the case, such as the circumstances of the case, the evidence continuity, results of any testing, progress of the case, invoicing and every other aspect of the forensic work. These systems are on a controlled secure server and along with the evidence stores which are accessed controlled form part of the means to ensure a safe and secure forensic service.

When there appears to be little evidence the scientist can only report on what they have/have not found. Scientist’s always adhere to a rule whereby all non destructive testing is performed first and destructive tests only done where necessary. In modern forensic science techniques are becoming increasingly advanced and so what might be undetectable evidence today could still be discovered in the future, and this is something we are now seeing with unsolved “cold cases” from the 1980’s/90s. Incidentally, in the UK, evidence is securely retained for 30 years even after a case is closed.

Training and Qualifications

There were also several questions this week related to becoming a forensic scientist, degrees and the various roles. Dillian Frost, Jaan Esken, Anthony James and Maria Chemodavnova all asked questions relating to this. In terms of the qualifications needed to work in forensic science, a Bachelors degree in any traditional science subject is often sufficient for getting a job in forensic science, although a lot of the scientists working in forensic labs around the world now have undergraduate degrees specifically in Forensic Science which have become more popular in the past 10-15 years.

It can be beneficial to do a pure science degree at undergraduate level and then specialise in forensic science at postgraduate level so that you have a broader knowledge and understanding which will be beneficial in the job market. There are a variety of postgraduate qualifications in forensic science across the UK, and the Chartered Society of Forensic Sciences accredits a number of UK and international courses. One of the MSc Forensic Science courses in the UK is offered by us here the Centre for Forensic Science at the University of Strathclyde, and if anyone would like any further information about this, you can find this at the course website or you are welcome to contact me at the university.

After studying people can go into roles as DNA analysts, fingerprint examiner, CSI/SOCOs, Forensic biologists, forensic toxicologist, forensic anthropologists or any number of other specialities but it is true to say that every forensic organisation will have their own procedures and specialisations and so scientists will always receive “on the job” training when they start working at a forensic laboratory regardless of prior qualification and experience.

A common misconception is that a scientist can do everything, this is very much not the case, each have an area of expertise and so someone would not be a SOCO and a toxicologist for example, and the individual interpreting blood patterns would not be the same as the person looking at toolmarks for example.

Another misconception is about pathologists/coroners being forensic scientists or having similar roles/training. A coroner is a medical doctor of many years’ experience and so their training, qualifications and role is very different to that of a forensic scientist (who is more lab based), or a SOCO (who is scene based). In fact, it is very rare for a forensic scientist to see a deceased body at all. Sharon L Thacker asked an interesting question related to this about information provided to the pathologist – they will be given a briefing by the CSM/SIO before entering the scene, but this is purely factually and should not affect their role which is to ascertain cause of death (normally done at the mortuary not the scene)

Donna Studley asks about Criminal Profiling; this again is a separate discipline sometimes referred to as forensic psychology. The training for this is substantially different with a more clinical basis. It is not widely used in the UK but these experts are affiliated with the criminal investigation process where needed, who along with the Police, SOCOs, Forensic Scientists and Pathologists all make up part of a bigger picture.

The recruitment industry is very competitive but vacancies in forensic science are not uncommon throughout the UK, especially for SOCOs in Scotland and DNA analysts in England. There are some people with forensic degrees who take completely different career paths but who find their degrees helpful because of the transferable skills, such as time management, communication and problem solving that a degree in forensic science can develop.

Impartiality, Integrity and resource management

Ernest Atlee and Paul Greasby both asked interesting and potentially complex questions and I have categorised these together here.

A fundamental concept of forensic science is that the scientist’s duty is to the court, regardless of whether they are technically paid by the prosecution or the defence. It is the job of the forensic scientist to evaluate any evidence in accordance with both the prosecution and defence’s hypotheses and using sound scientific principles which must be widely recognised to make their opinion on the evidence. A forensic scientist will not be allowed to give expert witness testimony if they do not meet the admissibility standards outlined in their country i.e. what is or is not allowed as evidence in court, in the America this is the Frye Test and Daubert Standard, in the UK this is governed in part by the Civil and Criminal Procedural Rules. A forensic scientist is working in insolation on evidence in only their own area of expertise, they should NEVER comment or draw any inference as to the guilt or innocent of an individual, this is a matter for the court. The scientist should always be impartial, unbiased and objective. There are many standards, quality assurance and measures in place to overcome any bias but there are still contentious schools of thought in relation to unconscious bia, which is harder to recognise and control. In the UK we use a method known as Case Assessment and Interpretation and this framework serves us well to minimise and potential bias or influence.

The resource situation in the UK is complex, substantial cuts to police budgets have led to more techniques being done “in house by the police” and very little profit in the market to enable a stable economy of forensic science by external providers. However, it is true to say that Police and Forensic Providers are still fully committed to maintaining the highest levels of quality and integrity

With limited budgets, police may not be able to request a full range of forensic tests on every exhibit in their investigations but scientists will advise on which items and evidence types to prioritise. For example, in a case of a “stranger rape” a staged approach might be used, where intimate swabs are examined first and only if no suspect’s DNA can be identified then they will move on to the next stage – the underwear. Alternatively, if it is an assault between two flatmates, the scientist may advise that it is not appropriate to look for hair/fibre trace evidence because the evidential value is low given that they live together and there is an expectation that they would have transferred hairs/fibres innocently. This is however a very difficult issue; it is true to say that, understandably, budgets for serious crime are much higher than volume crime and therefore more resources, including specialists, can be employed but only where it is deemed of potential evidential value.

In May 2019, the UK House of Lords’ Science and Technology Select Committee published its much-awaited inquiry report into Forensic Science Strategy which you can read here. It outlines some concerns in research, funding and leadership in forensic science in England and Wales. In addition, the forensic science community are pushing for statutory powers to be given to the Forensic Science Regulator, who is responsible for ensuring that high standards are maintained across the market, to make sure providers are delivering quality and consistency of service. It remains to be seen how the provision of forensic service in the UK will change over the next few years.

I just wanted to add one final thing, I have not answered any questions about the case as you will continue to receive more information as the course progresses. Please do continue to share your thoughts and ideas with each other though!

Sorry I couldn’t address everyone’s questions this time but many thanks for engaging with the content and I hope you find these answers of interest. There’ll be another opportunity to ask any questions in Week 3, in the meantime, enjoy!!

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This article is from the free online course:

Introduction to Forensic Science

University of Strathclyde