IT is painstaking scientific detective work which involves hunting for microscopic specks of blood or the tiniest fragments of fibres to try to solve often the most brutal and horrific of crimes.

For the last fifty years, forensic scientists at the University of Strathclyde have been involved in giving evidence in criminal cases, to both secure convictions and prove the innocence of wrongfully accused. Their expertise has been called on, not just in Britain, but from across the world.

The most high-profile cases include the so-called "Angel of Death" nurse Sister Jessie McTavish – who was found guilty of using insulin to murder patients in 1974 but later acquitted – the wrongly convicted Birmingham Six, the Oklahoma bombing and brutal murders, including Stephen Lawrence, Rachel Nickell and Damilola Taylor.

Strathclyde University's Centre for Forensic Science is highlighting the work carried out by its experts over the past few decades to mark the 50th anniversary of launching its forensic science postgraduate degree, which is the longest-established in the UK. More than 1,000 students have completed the course in that time.

A series of events is being held over the next few months to mark the anniversary, with experts in the field from the UK and the US delivering a series of guest lectures offering insight into the work of forensic scientists.

Dr Angela Gallop was appointed as the first Professor of Practice and Strategic Director for Forensic Science by the University last year.

One of the UK’s most experienced forensic scientists, she has been working in the field for around 45 years and said there had been many changes over that time – describing it as a “Cinderella area” when she first went into the profession.

In recent years, the popularity of television dramas such as CSI and Silent Witness have been credited with fuelling a boom in courses on the subject.

But Gallop said while it was good to see the profession in the limelight, the portrayal of it in dramas was not always entirely accurate.

“People go out to crime scenes and then magically the next minute they are in a laboratory with some evidence on the screen,” she said. “But there is an enormous amount of work in between – you have to be very careful not to lose evidence.”

Gallop, who specialises in cold cases, has been involved in a number of high-profile investigations.

One example is the murder of Lynette White, a 20-year-old who was stabbed more than 50 times in a flat in Cardiff in 1988. Three men were convicted of the crime – known as the Cardiff Three – but later released on appeal after it was proved the police had acted improperly.

But it wasn’t until 2002 that forensic evidence enabled the real killer – Jeffrey Gafoor – to be tracked down.

Gallop said: “One of the things we did was go to back to the crime scene, which had been redecorated twice in the intervening years. But we had all the pictures of the patterns of the original bloodstains.

“We took off a skirting board and the front door, where we knew there had been some blood, thought it might just be from the offender and we were able to detect some male DNA from some of the blood in both of these places

“It was very exciting to scrape away the paint laid on top of this blood and to reveal some of the blood underneath, which fortunately hadn’t been cleaned off before they redecorated.”

Gallop also uncovered crucial new evidence which helped in the conviction of two men, Gary Dobson and David Norris, over the murder of teenager Stephen Lawrence in 1993. This involved painstaking work which matched tiny fibres between Lawrence’s and the suspect’s clothing and also identified a tiny fragment of blood from the victim on one of the defendant’s jackets.

Former head of forensic science at Strathclyde University Professor Brian Caddy, who is now retired, said increasingly sophisticated technology developed over the past few decades had transformed the abilities of forensic science to uncover evidence.

He said: “This is particularly applicable to DNA. When DNA first started, you needed a blood splash about the size of a 10p piece [for analysis].

“But now you can do that with just a few cells – the sensitivity has increased enormously, although along with that comes the problem of potential contamination.”

Caddy has also worked on high-profile cases including the miscarriage of justice involving the Birmingham Six – six men sentenced to life in 1975 for the Birmingham pub bombings.

His work called into doubt forensic testing which concluded traces of the nitro-glycerine had been detected on the men’s hands, proving they had handled explosives. It was shown the test which found this could also have produced a positive result from the men handling a pack of cards containing a similar substance in the coating.

The evidence helped trigger a Home Office review of the case and the men finally had their convictions quashed in 1991.

Caddy was also involved in the case of the Oklahoma bomber Timothy McVeigh, who was executed by lethal injection in 2001, after being approached by his legal representatives to review forensic evidence.

He said: “I said I would read through the documentation – however the FBI carry out a well-known practice of sending you thousands of papers two weeks before the trial.

“I worked my way through them and there wasn’t really a lot of evidence to support the guy’s conviction in terms of forensic work. I didn’t give evidence in that case but he [McVeigh] admitted it himself.”

Caddy said he believed future developments in forensic science would include improvements in technology to allow DNA analysis to be carried out at the scene of a crime.

“They will take a sample and analyse it by new machines and the DNA database and be able to latch on much quicker than before to any suspect,” he said.