Crime scene scanner
A scanner which creates a 3D visualization of crime scenes is being designed at WUT’s Faculty of Mechatronics. Is Polish criminology going to go through a technological revolution?
Crime drama television series becoming Polish reality
In the “CSI: Crime Scene Investigation” TV series, the forensic science technicians are searching for evidence of crime in state-of-the-art laboratories using technologically-advanced equipment. The TV series became incredibly popular worldwide and had an immense effect on how people perceive police, its work and their investigative methods. In the US, we hear of the 'CSI syndrome'. “The popularity of forensic crime television shows supposedly gives rise to many misconceptions about the nature of forensic science and investigative procedures among jury members. The CSI effect is hypothesized to affect verdicts in two main ways: first, that jurors expect more forensic evidence than is available or necessary, resulting in a higher rate of acquittal when such evidence is absent; and second, that jurors have greater confidence in forensic and particularly DNA evidence than is warranted, resulting in a higher rate of conviction when such evidence is present”.1
Now it seems that advanced technology will be used not only in fictional TV series. The team from the Institute of Micromechanics and Photonics at the Faculty of Mechatronics is designing a scanner that will enable documentation, analysis (especially of blood traces), reconstruction and 3D visualisation of crime scenes. The device will not only be able to facilitate the work of forensic science technicians, but also improve the quality of the evidence material.
Up to this point, experts have mainly used photographic documentation, but it made it more difficult to reconstruct the topography of the site, the layout of rooms, objects and present evidence.
- Digital photography is with us for good in our everyday lives, and also with the Polish police forces. It is currently the quickest and cheapest way of image registration. Regardless of all its advantages, however, flat images also have their disadvantages which can be eliminated with 3D scanning. Scanners have long been used in criminology worldwide and they are used in Poland, as well, although fairly frequently. Until now, we have not had a solution dedicated to blood traces' analysis - says Dr Kamil Januszkiewicz from the Central Forensic Laboratory of the Police.
Three scanners at the crime scene
The solution might be provided by the consortium, which is led by the Warsaw University of Technology in which the Central Forensic Laboratory of the Police, University of Warsaw and Cybid general partnership (earlier Cyborg Idea Co.) are partners.The system comprises three scanners. One large, commercial, with low resolution and accuracy which is used for scanning entire rooms. There are also two additional scanners designed by us, Prof. Robert Sitnik from WUT’s Faculty of Mechatronics explains.
How will the system be used in practice?
If the system is calibrated then all you need do is press one button, Prof. Sitnik says. An overall scan is made first. Depending on the shape of the room, sometimes you need to make a few scans which are automatically joined together as long as there is an overlap. Then you use a situational scanner for fragments that do not need high resolution. Finally, you do a detailed scan of elements which require the most accurate images. – he describes.
The main objectives of this project is creation of not only scanners but also of an appropriate software. Scans from those three devices will automatically be making a single 3D model. In this way the person who collects the documentation of the crime scene will be able to visualize the room in 3D. There will be an option of increasing the size of the image and seeing all that is significant for the investigation is documented with proper resolution and accuracy, Prof. Sitnik explains.
What is more important, our solution does not suggest that we stop using traditional 2D photographs, but proposes using innovative technology developed by our partners from WUT and Cybid company from Krakow. It is simply another dimension – a 3D dimension. At the same time, at each stage of analysis, it will be possible to generate a traditional flat image, underlines Dr Kamil Januszkiewicz from the Central Forensic Laboratory of the Police.
Forensic revolution
Introduction of these scanners could revolutionise and facilitate work of the police. A 3D scanner should be a tool which allows experts who analyse blood traces a virtual walk around the crime scene and facilitates the reconstruction of the sequence of events, says Dr. Kamil Januszkiewicz. This way, multiple experts will be able to analyse a secured 3D reconstruction of the crime scene simultaneously. This might improve the quality and accuracy of the analysis. Another important fact is that even after quite some time, when the crime scene is no longer there, the stored and secured digital reconstruction will enable analysis, including new evidence that was not there previously, he adds.
In order to make it happen, the WUT team (together with its partners in the consortium) have to make sure that the system preserves the factual credibility of the documents – the person analysing the gathered material has to be certain that nobody fudged the data. We are working closely with the University of Warsaw’s Law Faculty. They will give us tips on how the procedures should be carried out according to the Polish law. It would be a total waste of time if we found out that our project was not lawful, Prof. Robert Sitnik sums up.
Even though 3D documentation is already being used in criminology, nobody has tried to preserve the blood traces with such detail ever before. The analysis of the origins of such stains is only a part of the forensic studies carried out as part of the preparatory proceedings and it helps a lot with determining the sequence of events. More than once, it determined the position of the victim in the moment they were attacked, and it also helps to single out traces important for the investigation when it comes to genetic analysis. By researching characteristic blood stains at the crime scene we can support or challenge the accuracy of the testimonies given by the suspects or witnesses. One must remember, however, that it is only a fragment of the larger puzzle and it will not replace a complex forensic analysis, says Dr Kamil Januszkiewicz from the Central Forensic Laboratory of the Police.
In the second half of 2014, the team led by Prof. Sitnik conducted a simulation of documenting a crime scene using their system. Until then, the team had been preparing the measuring systems and algorithms for merging data. The devices went through three cycles of optimization. In the final stage of the project, the documentation of the actual crime scene will be gathered together with the Central Forensic Laboratory of the Police.
These scanners can be used in other areas not just in crime detection as they can be used in direct sunlight. Such devices and this technology can have practical use in archaeology, medicine and various industries, foresees Prof. Sitnik.
1 Source: “Wikipedia : CSI effect”.