The Moment of Proof

A fingerprint left behind during a previous break-in at a food factory leads detectives to the brutal murderer of a security guard at the same location months later. With no murder weapon, no CCTV and no motive, police are in despair until incidents at the factory lead them to re-examine the old crime, and a former employee. Elsewhere, cutting-edge technology in the form of a DNA spray leaves a prolific motorbike thief with an indelible mark that he can't hide from the police.

A hotel guest book provides police with the names of members of an international drug smuggling network. Eagle-eyed officers match a hotel in Portugal to a selfie posted on social media by someone they suspect is a mule for the gang and are then able to make multiple arrests. Elsewhere, a gang of thieves who made off with £20,000 worth of perishables from a food factory are brought to justice after a car number plate left near an abandoned trailer allows them to be traced across the country.

A single fingerprint recovered from a fish and chips wrapper tossed on the ground is enough to place a gunman in a rural location miles from his home.

A jacket recovered from a suspect's home is found to have the DNA of two stabbing victims on it as police hunt for the person behind a series of seemingly unprovoked attacks. There's little for police to go on after a man is left to die in the street, and when the attacker strikes again, they are in a race against time to find the person responsible.

Fingerprints found at the scene of a burglary prove to be the missing piece of evidence detectives need to convict a man responsible for the murder of the flat's owner. After the man is found beaten to death in his own property, police use footprints found around his body to identify one assailant before putting together their case against his violent accomplice, whom they suspect of the killing.

Blood spatters found on a trench coat belonging to a suspect in an unrelated case of armed robbery links a callous killer to the murder of a wealthy pensioner. The police find just a business card and a cigarette butt at the crime scene, but then a detective spots the coat at the suspected robber's house and decides to run blood tests on a hunch. Also today, a detective's dogged approach pays off when he proves that a light aircraft that crashed, injuring three people, was too heavy for take-off.

A few spots of the victim's blood on a blue shirt convict a murderer when police deduce it was likely to be worn on the day of the killing. Detectives are left baffled by an apparently motiveless killing as they try to make sense of items left at the crime scene, but when they finally arrest a suspect, his vanity proves his undoing. Elsewhere, a rapper tells tales on himself when rap videos he posts online about his drug-dealing exploits mean the police come knocking at his door.

A blood-spattered hammer is the key to charging the police's prime suspect with a vicious murder. Police believe the man they have in custody is the killer, but with only circumstantial evidence, they need a breakthrough, Fortunately, they receive a mysterious call from the man providing their suspect's alibi. Also today, a drug-dealing gang is brought to its knees when one detective focuses on how the product is packaged to catch the men at the top.

A USB stick containing key information about the production and supply of illegal drugs is found in a raid of a respectable businesswoman's house. Authorities tell police that packages being posted labelled as so-called ‘legal highs' are a front for dealing narcotics online, so detectives set about finding the factory manufacturing them, before setting their sights higher. Elsewhere, after seeing an increase in guns designed to fire blanks converted into deadly weapons, police target the man responsible.

A single piece of A4 paper found on top of a hidden fax machine gives police the number of a shipping container used to smuggle millions of pounds' worth of drugs from Thailand. The men responsible for bringing it into the UK had been under covert surveillance for months, but until the fax was discovered, there was no way of proving the gang's involvement in the international drugs trade. Also today, a cheque for a mattress links a brutal killer to a body found at a Premier League football stadium.

A claw hammer recovered from a bin and contaminated with the DNA of both victim and killer is the final piece of the puzzle in a complex murder investigation. When the body of a woman is found, police speak to her lodger and become increasingly suspicious of his lies and strange behaviour, including the suggestion he has been tampering with her medication. Also today, the positive identification of a burglar who photographed himself at the crime scene leads police straight to his door.

A man is conclusively linked to a series of murders at music venues by a shoelace with traces of his final victim's DNA on it. After two people are set upon at a music festival by attackers with the same description, police are in a race against time to find their man, but then a third assault at a nightclub leaves them a vital clue. Also today, coded information buried within a spreadsheet reveals the man responsible for a campaign of hacking and blackmailing that targeted businesses.

An ice pick used to stab a man in the head on the street is recovered from the roof of a pub and brings a murderer to justice. Investigators are baffled after a man is brutally killed on the street and all they have to go on is some grainy CCTV until a woman tells them she thinks her husband carried out the slaying as revenge for a drug deal that went wrong. Elsewhere, an anonymous letter throws suspicion on a man who police believe may not only be storing guns, but manufacturing his own.

A car hidden deep within a scrapper's yard unlocks the riddle of a suspected gangland shooting at a secluded location. As police build their case against their prime suspect, they can't place him at the precise location of the shooting at the time of the murder. Also today, police secure the UK's first conviction for modern day slavery at a car wash after the owner's phone is shown to have tracked the victims' minibus as they were brought into the country.

A few tiny specks of grey paint help to solve not one but two brutal axe murders that have been baffling police. A determined detective has the paint tested and traced back to a supplier, which then leads him to the man who is behind both of the unsolved killings. Meanwhile, a bungling burglar is caught when his DNA is discovered on a rock used to smash a window at one of his break-ins. Police are then able to link him to several other similar crimes committed in the area.