INVESTIGATING a murder is a time-consuming affair which can stretch police resources to the full.

The responsibility of co-ordinating such an investigation falls on the shoulders of one individual: the senior investigating officer.

He, or she, is the person who gives out orders to all officers in a murder inquiry, from the PCs guarding the crime scene, to the detectives who eventually interview a suspect.

These are the officers glamourised in endless television crime thrillers.

But unlike the fictional creations, who rely on hunches or an unearthly sixth-sense to find the killer, the officers use a scientific approach to solve crimes.

Det Supt Simon Dinsdale is head of Essex Police’s major investigation teams covering the south of the county.

The officers under his command probe murders, rapes and kidnaps on a daily basis.

The straight-talking 55-year-old explained: “The senior investigation officer role is crucial. You are in charge and lead the team.

“Investigating murder is a science. It’s not done on feelings or gut instinct. It’s investigated in a methodical, structured way.

“I’m not like the TV inspectors such as Morse or Frost. I work to a clear plan and strategy.”

Once a suspected murder has been committed, the priority for the man in charge is to get to the crime scene as soon as possible.

He said: “Every scene is different and I always visit each one.

“A picture paints a thousand words, so being there and using your own eyes is crucial. You can assess the scene and take control of it.”

Once a victim is discovered, the “golden hour” kicks in, where officers race against the clock to secure vital forensic clues and speak to eye witnesses. House-to-house enquiries are started and officers look at any CCTV footage available.

He said: “We will be doing all of these things before the body is even lifted up.

“Ricky Wyatt – who was knifed to death in Little Lullaway, Laindon, on September 1, 2006 – was killed on a housing estate. So it was crucial to get witnesses as quickly as possible.”

Quite often, it is the victim themselves, their lifestyle and even their criminal history, who lead police to their killer.

Murder squad detectives use a triangle, with the victim, killer and crime scene forming its three points, to find their clues.

Mr Dinsdale said: “There is always a connection between the victim and the offender, the offender and the scene, and the victim and the scene.”

The detective, who has 28 years’ service, was one of five senior investigation officers using the triangle theory to find the Suffolk Strangler, Steve Wright. The serial killer murdered five prostitutes in Ipswich, in December 2006. He was jailed for life last February.

Det Supt Dinsdale recalled: “There were five girls found in different places. The connection was they were prostitutes and he was using them.

“While using the girls he took them to the area where their bodies ended up, linking him and them to the scene.”

But, murder squad detectives do not always have every point in their triangle. Sometimes, the victim’s themselves remain as elusive as their murderers.

The detective, who is based at Brentwood, was involved in the investigation of Basildon mum, Nicola Ray, 29, who went missing in May 2000 and has never been found.

Mr Dinsdale, who has never lost hope she and her killer will be located, said: “With a case like that you have to look at the obvious: Where she was last seen and where she was going to.

“We did a huge amount of house-to-house enquiries and looked at all the potentials, like whether she was dragged into a car and killed, but we got to a point where we had not found anything. It’s hard because you want to get justice. But we never close cases like that.”

But, for the hardened detective, the disappointment of unsolved murders is rare.

He travelled to Iraq twice in his hunt for child rapist and murderer Farik Far who killed his partner and mum-of-two, 32-year-old Inga Losiene, in Southend in 2005.

Farik was sentenced to 20 years.

And in 2005 he had a career defining moment when he successfully led the investigation into the murder of 63-year-old Norah Trott. A case that had been unsolved for 27 years.

Her killer, Wayne Doherty, is currently serving a 23-year sentence.

The murder was not only unique because of its age, but also because it fell into the 1 per cent of killings which are sexually motivated.

The 63-year-old, who ran a dress shop, was found bloodied and beaten by garages near to her Rochford home.

Mr Dinsdale said of the case: “That was a murder in the 20th century, but we had to get the case up to 21st century standards, with all the modern rules of evidence and disclosure. The case was a cause celebre in Essex, because it was the only one of its type that hadn’t been solved.

“As a police officer it was a delight to be able to give Norah’s family justice.”

The quest for justice for victim’s families is a huge motivation for Mr Dinsdale.

He said: “I couldn’t stop any of these people being murdered, unfortunately. What I can do is get justice for the victim and the family.

“It is a desperate time for the families and it so sad.

“I can patronise them by saying I know how they feel, but even with all my experience I can’t even begin to imagine what it is like for them.

“As for the murderers, they don’t have the same mindset as you or I.They are almost living in a parallel universe.”