1) asked to see if the document has been altered, if so, what are the details of the alterations?
2) if either of the two pens seized at the scene have been used to make the alterations?
yes in lab notes – even If the tests were inconclusive
No to make it non-bias
- I did an initial examination before performing the other things to see if there were any obvious changes made to the document that could be seen by the naked eye. This also helped to determine where to start my other examinations on the document and potemtially target certain areas with specific techniques eg. Where there was correction fluid used to blank out and re write a figure, I targeted that area with the VSC to determine if the same pen was used and to find out what was altered.
- I used raman as it can give insight into the molecular information (what elements make up the inks) – and not just the visual composition such as colour, of each ink I am testing, which I used to help determine the identification and differentiation between each ink sample provided.
- VSC was used for the analysis of the ink samples as it can reveal writing that has been removed, altered or added with a different ink, by the use of varying wavelengths and different light sources.
As it can be used to provide information on the chemical composition of the ink samples. For example, it can help to determine between different components within the ink samples provided, such as, dyes and solvents that are used within the pen to create the appearance of different colours.
An initial examination is the process of visually examining the sample for anything that can be seen by the naked eye. This gives the opportunity to identify any obvious alterations before starting techniques that can possibly cause destruction to the integrity of the sample.
VSC is a device that uses different light sources (UV, Fluorescent) and different wavelengths to help determine if any alterations have been made to a sample that is submitted to a lab. They also are used to uncover the use false legal documents such as passports/ID and counterfeit bank notes. The sample is placed into the machine and can be seen on a screen at the top of the device. When placed inside, the sample can then be examined under these different light sources to reveal the potential alterations.
It is a presumptive test so can’t be used in court for evidence
it lacks in sensitivity levels as it is seen to have weaker signals compared to many other spec methods. This can result in lack of evidence if other techniques are not used alongside this one