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Tuesday, August 18, 2009

CCTV at the heart of a wrongful conviction

" ... Many police forces in England and Scotland use video line-ups instead of live identity parades. This has made it cheaper and easier to run a line-up, and means that many more are being conducted. "There are currently up to 100,000 line-ups held per year, compared to around 2,000 at the time of the Devlin report," said Professor Tim Valentine, a leading eyewitness researcher at the University of London. "Errors are going to be proportionate to the number of procedures that are run, so I wouldn't be surprised if there are more errors now than there used to be."

The proliferation of CCTV cameras has also led to an increase in the availability of identification evidence. According to the Police Foundation, the UK now has more surveillance cameras than any other country in the world, and footage is used to solve around 160,000 criminal cases a year. When CCTV footage is used to identify someone in court, a police officer or relative may claim to recognise that person from the footage, a jury might be asked to compare the defendant to someone in CCTV images, or an expert can use facial mapping techniques to compare the defendant's face to that of the suspect.

Under the Turnbull guidelines - introduced in 1977 by a judge who found that visual identification "can bring about miscarriages of justice and has done so" - a judge has to warn the jury of the need for special caution when relying on such evidence. But eyewitness testimonies can still be one of the most persuasive types of evidence a jury will hear. "A witness standing up and saying: 'That's the man, I saw him, I will never forget his face' is extremely compelling to a jury," said Valentine. "Witnesses can be completely honest and be mistaken."

Psychological experiments have shown that facial recognition from CCTV can be as prone to error as traditional eyewitness evidence. In an experiment which looked at 600 identity parades, a fifth of eyewitnesses
picked the wrong person, Valentine said ... "

Read the complete story by clicking here.

1 comment:

Doktor Jon said...

The issue of 'cracked' trials that have collapsed through a lack of integrity in the CCTV recordings presented to court, is a very significant issue that has barely been touched upon.

Anecdotally, it's been suggested that only a tiny percentage of CCTV material ever finds it's way into a successful criminal trial, as the vast majority of recordings are essentially unfit for use in an evidential context.

Interestingly enough, whilst much effort is being expended on addressing the problems and issues surrounding recording formats and compression protocols, little tangible effort is being spent on improving the images at the camera end, as this is not widely recognised yet, as the building blocks of failure when it comes to getting video surveillance material through the Criminal Justice System.