Expert evidence is used to provide information to the court, which is likely to be outside of the knowledge of the magistrates, judge or jury. Opinion evidence can be given if the expert is qualified to provide such an opinion.
Duty of an expert witness
An expert is under a duty to help the court by giving opinion which is objective and unbiased in relation to matters within their expertise. The duty is one which is owed to the court rather than the party who is providing the instructions.
The Criminal Procedure Rules require an expert to provide certain information such as any potential conflict, an appeal which has been allowed due to a deficiency in their evidence, convictions or adverse judicial comment.
Will an expert always be heard?
Applications can be made to exclude expert evidence if it is argued its prejudicial effect outweighs its probative value. The courts have also indicated a willingness to exclude the evidence if it is insufficiently helpful to a jury in reaching its conclusions. The court can also reject evidence, for example, if it decides that the witness has not properly established his independence or has not complied with his duty to the court.
We will not hesitate to challenge experts called to give evidence by the prosecution if there is a prospect of exclusion.
What types of expert are used in criminal cases?
There is a wide range of relevant expertise in criminal law. This could include forensics such as DNA and fingerprints or footwear marks, facial recognition where identification from a still or CCTV is in issue, medical experts in respect of injuries, psychiatric or psychological reports, autopsies or gait analysis.
How do you find an expert?
We have a register of tried and tested experts in every discipline. An expert witness is not just an expert in their field, they have additional skills such as report writing and experience of giving evidence in court.
It is important, therefore, to get the right witness for your case and we can do this for you.
How can we help?
If you need specialist advice in relation to any criminal investigation or prosecution, from the initial investigation through to court proceedings, please get in touch. Call John Howey on 020 7388 1658 or email email@example.com. Let us help.Read More
The government this week announced that West Yorkshire Police has signed up to a new identity checking service, allowing fingerprints to be taken via an App.
The new service, already being used in a select number of force areas, with a further 20 going live before the end of this year, will remove the need for suspects to be taken to a police station to check their identity.
It is anticipated that this will reap benefits for frontline officers and suspects alike, freeing up police to continue with other duties and reducing needless detentions.
Police leaders have commented:
“Early examples of the new system in action include a firearms unit, who detained a driver after a short pursuit and were able to identify him as a disqualified driver, despite him giving false details. He was issued with a summons for three offences and his vehicle seized. The armed response unit returned to patrol within ten minutes, and without the mobile fingerprint scanner this could have resulted in the unit being out of action for four hours taking the individual to a custody suite.”
The new service works by connecting a small fingerprint scanner to a mobile phone App. Within seconds of taking a print the suspect’s identity can be checked across the two main police databases, allowing police to then deal with the suspect in the appropriate way.
While this technology has been available for a few years, reduced pricing has now made it affordable enough for a national rollout. Scanners that previously cost around £3,000 can now be purchased for under £300.
Liberty, the leading human rights organisation has been less enthusiastic, commenting that:
“This scheme is part of a pattern of the police using radical privacy-invading technology without proper public consultation or meaningful parliamentary oversight. Much like the facial recognition technology that is increasingly being deployed by police forces, it is being presented to us after the event and with little fanfare and is being made available to more and more officers across the country. In this case, we learned about it via a sneaky gov.uk post early on a Saturday morning.”
Although there are clearly benefits to everyone involved, there remain concerns. Little is known about what will happen to the data after it has been checked; for example, if you are not already on either data base but are stopped and checked, what happens to your data? Will the technology only be used when there is doubt about a person’s identity or will it be used indiscriminately? As with any system there remains the potential for human error, not least when data is being added to the databases.
There are important protections for suspects that are to be found in the Police and Criminal Evidence Act 1984. However, ensuring that these protections are adhered to can be difficult in away from the police station. If you have any concerns about the use of these powers, please contact us to discuss further. Where fingerprint identification is being used evidentially by the prosecution, we always take particular care to ensure that the law has been complied with.
How We Can Help
If you are someone facing criminal proceedings, contact us as soon as possible; firstname.lastname@example.org or 020 7388 1658. Our solicitors are well versed in this aspect of the law and will ensure your best defence.Read More
A new technique for identifying criminals could be in use ‘within months’ following years of development by Sheffield Hallam University. But what is it and could there be problems?
Mass Spectrometry: analysing the ridges of the fingerprints
Fingerprints on crime scenes, weapons and stolen property have been the undoing of many a criminal over the years. With evidence being corroborated by DNA, CCTV and cell-site analysis the commission of crime, for the petty criminal at least, is getting harder and harder to get away with.
The latest development in fingerprint testing could potentially take prosecution evidence to a new level. Researchers have developed a technique called ‘mass spectrometry’, which analyses traces of substances ‘on or within the ridges of the fingerprints’.
It is claimed that the technique can reveal whether the print belongs to a male of female, whether there are traces of drugs and whether a person has handled a condom, the latter claim being so specific that the brand can be identified. This is a significant leap on from the current position of simply identifying the owner of a particular print.
Certain crimes should therefore be more detectable, for example a defendant denying that he/she has handled drugs will have a far more difficult time in court if the evidence shows that drugs have been taken.
Our concern is that unless the match is so precise it will be difficult to show a direct correlation between drugs seized and drugs taken. Any given batch of drugs is likely to have differences which could, of course, be reflected in the print it leaves. However, taking the condom claim, which is clearly intended to improve the quality of evidence in rape and sexual assault cases, an item such as that will be produced in a factory with rigorous quality controls. Deviations in product are, we expect, likely to be far fewer.
That of course brings us on to the obvious question; although the test can deduce that a suspect handled a brand ‘A’ condom is it able to provide any clue as to when? What if the complainant is mistaken and actually a brand ‘B’ condom was used in the assault? Will that negate their complaint and offer a defence.
Current problems associated to fingerprint evidence
Similar problems already exist with the use of fingerprint evidence as we currently know it. Whilst a fingerprint may well show that a suspect has a link to a particular place it does not provide the date/time on which it was left at the scene. Unless mass spectrometry is able to provide a specific date and time as to when the identified substance was handled by the suspect its use will face the same limitations as current methods. Although a significant jump forward the value of the evidence it produces will be limited unless there is other corroborating evidence against a suspect.
For years DNA was seen as infallible but recent reports show that the evidence it yields is not as clear-cut as it could be. Although an admirable leap forward and one which will no doubt be refined in years to come we should exercise caution in the reliance of mass spectrometry evidence as being the smoking gun in cases.
The biggest limitation though is the database itself. A print or sample is only ever going to be effective if there is a match on a database entry. There are numerous unsolved crimes committed each year ranging from murder and rape to theft and public order. Some will naturally lend themselves to having some form of physical evidence such as DNA or fingerprint. However, even a murder case with a fingerprint on the weapon and the perpetrator’s blood on floor means nothing if that person is not on the police database.
Duncan Roberts, SolicitorRead More