Why investigate a crime from 1926?

WHO, WHAT, WHY? The Magazine answers...

Emma Smith (middle row, far left) who disappeared in 1926

Police have reopened the case of a teenage girl who disappeared over 80 years ago. But assuming everybody involved is dead, what is the point?

Emma Alice Smith was last seen cycling from her home in Waldron, east Sussex, to the local train station in 1926. Despite a police investigation at the time, her body was never found.

The case has been reopened after her great-nephew came to police saying that a dying man had confessed to murdering Emma and dumping her body in a local pond.

But with eight decades having passed, no-one concerned is still alive. So why are police investigating it now?

The police do not have any statutory obligation to follow up any cases that go back this far. But there are three key reasons why they may decide to do so.

THE ANSWER Request from family Symbolic that murder investigations are never closed It's, administratively, a successful case

The police are allowed to respond to the plea from the girl's descendants.

When a family comes to the police with a strong belief that a mystery can be uncovered then detectives will endeavour to do so, as Detective Inspector Mike Ashcroft of Sussex police explains.

"We're not obliged by statute to follow something like this up but if the family comes forward it's very difficult to say no. In this case, it's not going to sit on top of the tree of priorities but we'll do what we can."

Then there is the symbolic element - the power of the idea that the police can solve an offence as old as this

Prof Martin Innes, director of the Universities' Police Science Institute, says that the idea the police can go back in time to uncover crimes is very important. It demonstrates that there is no expiry date on an offence, however far back in time it may be.

"There's always been a philosophy in British policing that murder investigations are never closed."

Exceptional case

The third reason is administrative. If the case is solved, the police can record it as another crime off the books.

"From an administrative perspective, it is another crime that police can report as having detected successfully," says Prof Innes.

The mystery of Emma Alice Smith's disappearance is exceptional even among cold cases, those revisited after time has passed.

For the majority of unsolved crimes - think Waking the Dead - the results can be very positive when revisited. Often people's circumstances change, relationships evolve, and conscience makes reluctant witnesses come forward.

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"The police have realised that if you allow time to pass then people who previously wouldn't have co-operated may do so after a length of time. That same principle has been applied to recent investigations like Operation Trident - tackling gun crime in London," says Prof Innes.

The other major driver for reopening old cases is the advances in forensic technology, particularly DNA developments which allow the tiniest piece of evidence to be identified as belonging to someone. These improvements have helped in solving the murders of Rachel Nickell and Vicky Hamilton, 16 years and 17 years respectively later, as well as many others.

But in this case, of the missing Emma Smith, no chance of a previously-unheard of witness or DNA advances will transpire now. It is simply a matter of finding her body for the sake of her family.