109 Fun Facts About Forensic Science

The word "forensic" comes from a Latin word meaning "of" what?

The forum. Roman trials and public hearings were held in the forum, and "forensics" still names the art of formal debate as well as crime-scene work.

The Washing Away of Wrongs, a 1240s handbook for coroners, was written in which country?

China. Song Ci, a Song dynasty judge, wrote what is widely regarded as the first treatise on forensic medicine, hoping careful examination of the dead would stop innocent people being condemned.

What gave a killer away when every man in a 13th-century village was told to lay out his sickle?

Flies gathered on his sickle, drawn by blood too faint to see, and its owner confessed. The case, written down in the 1240s, is the oldest known use of insects to solve a crime.

What did suspects in ancient India have to spit out as a crude lie-detection test?

Dried rice. A frightened liar was thought to make less saliva, so grains that came out dry or stuck in the mouth were read as a sign of guilt.

John Toms was convicted of murder in 1784 after a pistol wad matched what item in his pocket?

A torn newspaper. Pistols of the day needed a wad of crushed paper to hold powder and ball in the muzzle, and the wad taken from Edward Culshaw's head wound fitted the torn sheet exactly.

Wood expert Arthur Koehler matched a homemade ladder to a floorboard in the suspect's attic in which famous case?

The Lindbergh kidnapping. Koehler showed that one rail of the ladder left at the house had been cut from a board in Bruno Hauptmann's attic, with nail holes that lined up with the joists.

The Marsh test of 1836 let chemists prove which poison, nicknamed 'inheritance powder', was present in a body?

Arsenic. James Marsh devised the test after a man accused of poisoning his grandfather's coffee was acquitted, because the chemical proof Marsh had prepared spoiled before the jury saw it.

Mathieu Orfila, royal physician to France's Louis XVIII, is often called the father of which forensic field?

Toxicology. Orfila's 1814 treatise on poisons showed how to find them chemically in a body, and courts began calling him as an expert, most famously at the Lafarge murder trial of 1840.

Ballistics pioneer Calvin Goddard test-fired police machine guns to clear officers of which gangland killing?

The St. Valentine's Day Massacre. Some of the gunmen had dressed as policemen, so Goddard tested the Chicago force's Thompsons and showed none was used; the jury foreman then paid for a crime laboratory for him.

Alphonse Bertillon's identification system was based on what?

Body measurements. In 1884 his cards of head and limb measurements caught more than 240 repeat offenders, and police forces across Europe and the Americas took up the system.

Bertillon's flawed handwriting evidence helped wrongly convict which famous defendant?

Alfred Dreyfus. Bertillon was no handwriting expert, yet he told the court the captain had imitated his own handwriting to disguise the spy's note, a theory he called self-forgery.

Which animal has fingerprints so similar to a human's that they are hard to tell apart even under a microscope?

Koala. Marsupials and primates evolved their ridged fingertips separately, probably because both climb and grasp, so a koala's print shows the same loops and whorls as a person's.

Henry Faulds wrote the first paper on fingerprint identification in 1880 while running Tsukiji Hospital in which Japanese city?

Tokyo. The Scottish missionary doctor grew curious after noticing potters' fingermarks pressed into prehistoric pottery, and his letter to Nature proposed using printing ink to record prints.

Francis Galton, who put the odds of two fingerprints matching at 1 in 64 billion, also coined which notorious term?

Eugenics. Galton coined the word in 1883 for his idea of improving humanity through selective breeding, a notion later used to justify forced sterilisation.

Croatian-born police official Juan Vucetich built the first working fingerprint files and solved a murder with them in 1892 in which country?

Argentina. A bloody thumb mark on a door showed that Francisca Rojas, who had blamed a neighbour for killing her two children, was the murderer herself, and she confessed.

Azizul Haque and Hem Chandra Bose helped devise the Henry fingerprint classification, named after their British police chief, in which Indian city?

Calcutta. Edward Henry carried the system to Scotland Yard under his own name; only in 1926 did he write that Haque had contributed more than any other member of his staff.

Fingerprints that are invisible to the naked eye and need chemical or powder development are called what?

Latent prints. They are left by the sweat and oils on a fingertip, which is why a fine powder brushed over the surface sticks to the ridges and shows the pattern.

Fumes from which household product make hidden fingerprints show up on guns and bottles?

Superglue. Its fumes harden into a white film along the ridges, an effect a Japanese police examiner noticed by chance in 1977 while mounting hairs on a glass slide.

Identical twins have different fingerprints because the ridge patterns are shaped at which stage of life?

In the womb. The ridges form from about the third month of pregnancy, and each finger's position and the pressures around it differ, so twins with the same DNA end up with different prints.

Being born without fingerprints is nicknamed 'immigration delay disease' after a woman struggled to enter which country?

The United States. Its border rules require foreign visitors to be fingerprinted, and when dermatologist Peter Itin looked into the Swiss woman's case in 2007 he found that several relatives had also been born without prints.

Paul Uhlenhuth's 1901 precipitin test allowed investigators to distinguish what?

Human from animal blood. Its first big case, in 1901, convicted a German carpenter who had explained away the stains on his clothes as wood dye and cattle blood.

Luminol reveals hidden blood by reacting with what?

The iron in hemoglobin. It acts as a catalyst for luminol's light-giving reaction, but bleach, copper and even horseradish can set it off too, so a glow alone never proves blood.

What colour does luminol glow when it reacts at a crime scene?

Blue. The light comes from a chemical reaction rather than heat and fades quickly, so investigators darken the room and photograph the glow straight away.

Which novelist studied law in Prague under Hans Gross, whose 1893 handbook pioneered scientific crime investigation?

Franz Kafka. He sat through Gross's criminal-law lectures between 1902 and 1905, a decade before writing The Trial, whose hero is prosecuted without ever learning the charge.

Forensic linguistics helped the FBI catch which bomber after his own brother recognised turns of phrase in his published writing?

Ted Kaczynski. When the Unabomber's manifesto was printed in 1995, his brother David dug out family letters with similar phrasing, and the FBI's comparison of the two supported the search warrant for his cabin.

Edmond Locard is remembered for the principle that every contact leaves what?

A trace. Locard proved the point in 1912, when face powder scraped from under a bank clerk's fingernails broke his alibi for strangling his girlfriend.

Which part of an adult skeleton do forensic anthropologists rely on most to tell whether it was male or female?

The pelvis. A woman's is broader with a wider opening, shaped by the demands of childbirth, so examiners look there first and treat the skull as a less reliable second check.

Which staple of police work did French police official Alphonse Bertillon standardise in 1888?

The mug shot. Bertillon fixed the lighting and angles and paired a full-face view with a profile on every card, so that pictures of one person taken years apart could be compared.

Frances Glessner Lee's Nutshell Studies of Unexplained Death are what?

Dollhouse crime scene dioramas. Lee built them from the 1940s at a scale of one inch to the foot, as composites of real cases, so detectives could practise reading a death scene for clues.

Al Capone went to prison in 1931 after forensic accountants proved which crime against him?

Tax evasion. Treasury agent Frank Wilson found three old ledgers at the back of a filing cabinet that tied gambling profits to Capone, and the gangster was sentenced to 11 years.

Heiress Frances Glessner Lee paid for a department of legal medicine at which university?

Harvard. Her friend George Magrath, a Boston medical examiner, drew her into the field, and together they campaigned to have coroners replaced by medically trained examiners.

Who discovered DNA fingerprinting after a "eureka moment" looking at an X-ray film on 10 September 1984?

Alec Jeffreys. The film unexpectedly showed both likenesses and differences between members of his technician's family, and within half an hour he saw it could tell individuals apart.

Before it ever solved a murder, DNA fingerprinting was first used in 1985 to settle what kind of case?

An immigration dispute. Officials doubted that a 13-year-old returning from Ghana was really the son of the woman he came to rejoin in London, and the test showed that he was.

In 2018 detectives identified which long-hunted serial killer by uploading crime-scene DNA to a genealogy website?

The Golden State Killer. The upload found only distant cousins, so genealogists built family trees until they reached Joseph DeAngelo, then 72, whose discarded DNA matched.

How did Colin Pitchfork initially evade the mass DNA screening of local men?

A colleague gave a sample in his name. Ian Kelly took the test with a doctored passport for £200, then talked about it in a pub, and a woman who overheard went to the police.

Richard Buckland, the first suspect cleared by DNA, had already done what?

Confessed. Buckland, 17, had admitted one of the two murders in the Pitchfork case, but his DNA matched neither, so police turned to testing thousands of local men instead.

Modern DNA profiling relies mainly on which highly variable stretches of DNA?

Short tandem repeats. Each is a short run of DNA letters repeated many times over, and because the number of repeats at each site differs between people, counting them at a set of sites gives a profile.

Which technique used to amplify tiny DNA samples was developed by Kary Mullis in 1983?

Polymerase chain reaction. Mullis said the idea came to him on a night drive through northern California, and it won him a share of the 1993 Nobel Prize in Chemistry.

Which British royal gave the blood sample whose DNA helped identify the remains of Russia's murdered Romanovs in 1993?

Prince Philip. His grandmother was a sister of Tsarina Alexandra, so his mitochondrial DNA, which is handed down only by mothers, matched that of the empress and her children.

Which FBI database, authorised by Congress in 1994, lets crime labs across the US compare DNA profiles?

CODIS. The Combined DNA Index System holds profiles without names, so when a crime-scene sample matches, the laboratory that loaded the profile has to be asked whose it is.

Police in which country pioneered familial DNA searching, catching a 1988 murderer through his teenage nephew's profile in 2003?

The United Kingdom. The 14-year-old had not even been born when Lynette White was killed in Cardiff, but his profile was close enough to lead detectives to his uncle, who pleaded guilty.

What nickname is given to the University of Tennessee site where donated cadavers are left outdoors to study decomposition?

The Body Farm. Anthropologist William Bass set it up after badly misjudging how long a Civil War colonel had been dead, and crime writer Patricia Cornwell used the name as the title of a novel.

John Larson built the first polygraph in 1921 while working as what?

Police officer. Larson had joined the Berkeley force a year earlier with a doctorate in physiology, but he came to regret how his machine was used and called it a Frankenstein's monster.

Polygraph pioneer William Moulton Marston is better known for creating which comic hero?

Wonder Woman. Her golden lasso makes captives tell the truth, and a court's 1923 refusal to admit Marston's own lie test in a murder case set the Frye standard for scientific evidence.

TV serial killer Dexter Morgan holds a day job with the Miami police analysing what?

Blood spatter. Dexter comes from Jeff Lindsay's novels, and his rule of killing only murderers who have escaped justice is what let audiences root for him.

What name is given to the spiral grooves inside a gun barrel that leave telltale scratches on every bullet fired?

Rifling. The grooves spin the bullet so it flies straight, and because the cutting tool wears a little with every barrel it makes, no two barrels mark a bullet in quite the same way.

Whose murder trial turned on the defence claim that police had contaminated or planted the blood samples used for DNA tests?

O. J. Simpson. His lawyers barely disputed the DNA matches themselves; they attacked the careless way the blood had been collected and stored, and the jury acquitted him.

Bite-mark evidence helped convict which serial killer of the Chi Omega sorority murders?

Ted Bundy. At his 1979 trial in Miami, forensic dentists matched a bite on victim Lisa Levy to casts of his teeth in front of the jury, and he was sentenced to death.

Bite marks were first used as evidence in North America during which proceedings?

The Salem witch trials. In 1692 the court had the minister George Burroughs's mouth prised open so his teeth could be compared with marks on the girls who accused him, and he was hanged.

A skeleton found under a Leicester car park in 2012 was confirmed by DNA as which English king?

Richard III. His mitochondrial DNA matched that of Michael Ibsen, a Canadian-born furniture maker descended from the king's sister Anne, and the skeleton's curved spine fitted the old accounts.

In 1668 Francesco Redi sealed rotting meat in jars to disprove which long-held scientific belief?

Spontaneous generation. Maggots appeared only on meat left open to insects, never in the sealed or gauze-covered jars, so they had to hatch from eggs and could not spring from the decay itself.

The earliest surviving offender profile was written in 1888 by surgeon Thomas Bond about which killer?

Jack the Ripper. Bond judged from the wounds that the killer had 'no scientific nor anatomical knowledge', not even a butcher's, dismissing the idea that a surgeon was at work.

The title 'coroner' goes back to medieval English officials who guarded the legal interests of whom?

The Crown. The office was created in 1194 as 'keeper of the pleas of the Crown' to protect the king's property, and holding inquests on dead bodies was only one of its duties.

In an 1816 Warwick murder case, an impression left in damp earth was matched to which item of a farm labourer's clothing?

His patched breeches. The corduroy weave and a sewn patch had printed themselves in the mud beside the pool where a maidservant was drowned, and grains of wheat there pointed to a man who had been threshing.

Henry Faulds sent his fingerprint method to which famous naturalist, who passed it on to Francis Galton?

Charles Darwin. Too old and ill to take it up himself, he passed the letter to his cousin Galton, who went on to write the book Finger Prints.

Which murderer was caught after mailing a TV station a floppy disk whose hidden data named his church?

The BTK Killer. Dennis Rader had asked police whether a floppy disk could be linked to its sender, believed their reply that it could not, and sent one that still held his church's name and 'Dennis'.

Edmond Locard, who opened a pioneering police laboratory in Lyon, was nicknamed after which fictional detective?

Sherlock Holmes. Locard was delighted to be called the Sherlock Holmes of France, and in 1921 Arthur Conan Doyle himself came to see his Lyon laboratory.

What name is given to jurors' inflated expectations of forensic evidence, blamed on a hit TV crime franchise?

The CSI effect. Prosecutors complain that jurors now expect forensic proof in every case, yet studies that have tested the idea on jurors have found mixed results at best.

In the first 375 US convictions overturned by DNA, which factor did the Innocence Project find most often?

Mistaken eyewitnesses. Wrong identifications featured in about seven in ten of those cases, which is why reformers press for line-ups run by officers who do not know who the suspect is.

An autopsy finding that only one of 23 stab wounds was fatal followed the assassination of which Roman leader?

Julius Caesar's autopsy, often called the first in recorded history, found that the only fatal blow was the second one, struck near his ribs.

Which American Revolution hero identified General Joseph Warren's exhumed body by a false tooth he had wired in?

Paul Revere, a silversmith who dabbled in dentistry, recognised his own wire in the mouth of his friend, who had been killed at Bunker Hill and buried on the battlefield for the better part of a year.

Bulgarian dissident Georgi Markov was killed in London in 1978 by a poison pellet delivered with which everyday object?

An umbrella was dropped behind Markov at a bus stop by Waterloo Bridge just after he felt a sting in his thigh. The platinum pellet later found in his leg was only 1.7 millimetres wide.

Text-analysis software helped unmask Robert Galbraith, credited author of The Cuckoo's Calling, as which novelist?

J. K. Rowling was confirmed when two professors ran the crime novel through programs comparing it with her earlier books. The original tip-off was a leak from her own law firm, passed to a reporter on Twitter.

Paris police held Vincenzo Peruggia's fingerprints yet never matched the thumbprint he left stealing which painting?

The Mona Lisa's protective glass carried the print of a former Louvre worker when the painting vanished in 1911. Staff were fingerprinted, but he was overlooked and kept it in a trunk for two years.

A London nurse spotted a baby's thallium poisoning thanks to symptoms described in a novel by which crime writer?

Agatha Christie had worked in a wartime hospital dispensary, and The Pale Horse describes the poison's effects so exactly that nurse Marsha Maitland recognised them in a child flown in from Qatar in 1977.

Tests mistaking sound-deadening spray for blood helped convict Lindy Chamberlain, who said which animal took her baby?

A dingo took nine-week-old Azaria from the family tent, a coroner finally ruled in 2012. Lindy had spent more than three years in prison on the strength of the flawed tests on the family car.

DNA from hairs left in an old book helped confirm that bones under a Polish cathedral belonged to which astronomer?

Copernicus lay in a lost grave in Frombork Cathedral that archaeologists hunted for two centuries. The matching hairs were in one of his own books, carried off to Sweden as war booty in the 17th century.

Anna Anderson, shown by DNA after her death to be a Polish factory worker, claimed to be which Russian grand duchess?

Anastasia's supposed survivor was really Franziska Schanzkowska: DNA from Anderson's hair and a hospital tissue sample matched a great-nephew of the missing Polish worker, not the Romanovs.

The 1930s Drunkometer, forerunner of the police breathalyser, collected a suspect driver's breath in what?

A balloon caught the breath, which was pumped through a chemical solution that changed colour more the drunker the driver. Rolla Harger of Indiana University developed the device in 1931.

Which 1930s bank robber paid a surgeon to burn off his fingerprints with acid, yet was still identified by them?

John Dillinger's scarred fingertips still matched his arrest records when lawmen shot him outside Chicago's Biograph Theater in July 1934. The surgeon had charged $500 a hand.

Which American author built the courtroom climax of his novel Pudd'nhead Wilson around fingerprint identification?

Mark Twain had already had a killer identified by a thumbprint in a tale in his 1883 memoir Life on the Mississippi, ten years before the novel appeared.

Critics gave which mocking nickname to the Warren Commission's finding that one shot wounded both Kennedy and Connally?

The magic bullet, exhibit CE 399, turned up on a stretcher in a corridor at Parkland Hospital. Defenders point out that Connally sat lower and further inboard than Kennedy.

Which radioactive element, slipped into a teapot at a London hotel, killed former Russian agent Alexander Litvinenko?

Polonium is so hard to detect that doctors first suspected thallium, and the real cause was identified only hours before his death. He drank the dose in green tea at the Millennium Hotel's Pine Bar.

Which poison, hidden in Tylenol capsules in Chicago in 1982, led to federal anti-tampering laws?

Cyanide was suspected as soon as an investigator smelled almonds in a victim's bottle. At least seven people died, the poisoner was never identified, and powder-filled capsules were phased out.

Pathologist Bernard Spilsbury found fame testifying against which doctor, a fugitive caught by wireless telegram?

Dr. Crippen was sailing to Canada with his lover, who was disguised as a boy, when the ship's captain wired London. Spilsbury identified the cellar remains from a scar on a small piece of skin.

Modern paper whiteners and polyester bindings exposed which 1983 scoop bought by Stern magazine as a forgery?

The Hitler Diaries had cost the German weekly nine million marks before proper lab tests were run. Their forger, memorabilia dealer Konrad Kujau, was sent to prison.

Disputed ballistics tests on a Colt pistol helped convict which two anarchists, executed for murder in 1927?

Sacco and Vanzetti became a worldwide cause. A 1961 retest suggested the pistol found on Sacco did fire a fatal shot, though doubts about how the exhibits were handled have never gone away.

Disputed DNA on a kitchen knife and a bra clasp was central to the Italian murder trials of which American student?

Amanda Knox and Raffaele Sollecito were definitively cleared by Italy's top court in 2015, which cited stunning flaws in the investigation. Experts had said the DNA specks pointed to contamination.

Scans in 2001 found an arrowhead in the shoulder of which 5,000-year-old Alpine mummy, pointing to murder?

Ötzi bled to death after the arrow shattered his shoulder blade, and a matching tear in his coat showed where it struck. He had been studied for a decade before anyone spotted the wound.

Defence lawyers probe for breaks in which paper trail, listing everyone who has handled an exhibit since collection?

Chain of custody logs every hand-over, and if nobody can prove who held an exhibit at some point, the defence can ask for it to be ruled inadmissible. Sport uses the same system for athletes' drug-test samples.

Which cell structures carry their own loop of DNA, passed down only by mothers and tested when remains are degraded?

Mitochondria number in the hundreds per cell, so their DNA often survives when the two nuclear copies are too damaged to read. It is shared down a whole maternal line, so it cannot single out one person.

Which letter names the autopsy incision that runs from each shoulder to the breastbone and then down the abdomen?

The Y-shaped cut continues all the way to the pubic bone, swerving around the navel. Shears then cut through the ribs so the breastbone can be lifted out and the heart and lungs seen in place.

Which droopy-eared dog breed's skill at following a human scent trail is accepted as evidence in some courts?

The bloodhound was already tracking thieves and poachers by their foot scent in the 16th century, and it can pick out one person's trail over long distances and long after it was laid.

Which TV crime drama features goth forensic scientist Abby Sciuto, played for 15 seasons by Pauley Perrette?

NCIS bases Abby at the Washington Navy Yard, where the cheerful goth in pigtails covers ballistics, digital evidence and DNA for the naval investigators.

In the film The Silence of the Lambs, which insect is found lodged in a murder victim's throat?

A death's-head moth later betrays the killer when Clarice Starling spots one in his house. He had been importing the live caterpillars from Suriname.

Which novelist introduced medical examiner Kay Scarpetta in Postmortem, based on real stranglings in Richmond?

Patricia Cornwell took a job at Virginia's chief medical examiner's office in 1985, and saw three novels rejected before Postmortem came out in 1990.

Scopolamine and sodium thiopental have both been tried on suspects under which hopeful two-word nickname?

Truth serum took off in the 1920s, after an obstetrician noticed that women sedated with scopolamine in childbirth answered questions with unusual candour. No drug has ever been proven to work reliably.

The word autopsy, now a pathologist's examination of the dead, comes from Greek roots meaning to do what?

See for oneself is the literal sense of the Greek autopsia, from autos, self, and opsis, sight. The word entered English in the 1650s meaning an eye-witnessing.

Algor mortis, which helps a pathologist estimate the time of death, is the steady change in which property of a body?

Temperature drops about 2 °C in the first hour after death and roughly 1 °C an hour after that, until the body matches its surroundings. Algor is Latin for coldness.

The 'Phantom of Heilbronn', a serial killer whose DNA turned up at 40 crime scenes, proved to be contamination on what?

Cotton swabs from one factory carried the DNA of a woman who worked there. Police in Bavaria bought theirs elsewhere, which is why the phantom never seemed to strike in that state.

DNA tests wrongly suggested Lydia Fairchild was not her own children's parent because of which two-genome condition?

Chimerism meant Fairchild's skin and hair carried one set of DNA while her cervical cells carried another, the set her children had inherited. Her lawyer cracked it after reading of a Boston woman with the same condition.

The FBI wrongly declared lawyer Brandon Mayfield's fingerprint a '100 percent match' to a 2004 bombing in which city?

Madrid's train bombers left prints on a bag of detonators, and an FBI database search threw up Mayfield among twenty candidates. He was held for two weeks before Spanish police named another man and the bureau apologised.

Los Angeles detectives confirmed the 'Grim Sleeper' serial killer's identity using DNA from which discarded item?

A pizza slice was collected by an undercover detective posing as a waiter at a restaurant where the suspect ate. A relative's profile in California's database had first pointed investigators to his family.

Saliva kept since 1987 let DNA testing identify truck painter Gary Ridgway as which Washington State serial murderer?

The Green River Killer was arrested in 2001 as he left the truck factory where he worked. He pleaded guilty to 48 murders in a deal that spared him execution in return for locating victims' remains.

Chicago killers Leopold and Loeb were traced in 1924 through an unusual hinge on what item dropped near the body?

A pair of glasses lay near 14-year-old Bobby Franks, and only three customers in the city had bought frames with that hinge. Nathan Leopold said his must have fallen out on a bird-watching trip.

A fracture of which horseshoe-shaped bone in the neck strongly suggests that an adult victim was strangled?

The hyoid, also called the tongue-bone, is so well shielded by its position that it is not easily broken. In children it is still flexible, so strangulation may leave it whole.

Loops, arches and which third pattern, seen on about a third of fingers, make up the basic fingerprint types?

Whorls account for 30 to 35 percent of prints, against 60 to 65 percent for loops and only about 5 percent for arches. Their sub-types include the double loop and the peacock's eye.

Investigators cracked the 1993 World Trade Center bombing after finding what on a fragment of the bomb van's axle?

The vehicle's VIN led agents to a Ryder rental van that one of the plotters had reported stolen. He was arrested when he came back to the rental office to claim his deposit.

In the Kastle-Meyer test used at crime scenes, a sample turns which colour within seconds if it is probably blood?

Pink appears because blood speeds up a reaction that turns a colourless chemical back into the indicator dye phenolphthalein. Copper and nickel salts can trigger it too, so a positive only counts as presumptive.

Which chemical reveals old fingerprints on paper by reacting with amino acids in the residue to stain them purple?

Ninhydrin's stain is called Ruhemann's purple after the chemist who discovered the compound in 1910. Swedish investigators proposed using it on fingerprints in 1954.

Which light-bending property of glass fragments do crime labs measure to check whether two pieces share a source?

Refractive index is measured by immersing a fragment in liquids of known values. A mismatch rules out a common source, while density and elemental tests can back up a match.

Which Austrian doctor won a Nobel Prize for sorting human blood into the groups A, B and O in 1901?

Karl Landsteiner had noticed a year earlier that blood from two people can clump on contact. He went on to help identify the Rhesus factor and the polio virus.

Under the Daubert ruling, who acts as 'gatekeeper' deciding whether expert scientific evidence reaches a US jury?

The trial judge must make sure expert testimony rests on a reliable foundation. Before Daubert, courts often simply let juries hear both sides' experts; a 1999 ruling extended the duty to every kind of expert.

Which French ex-convict founded the Sûreté detective force and later ran the first known private detective agency?

Eugène Vidocq turned his underworld contacts into a detective career, and his life story inspired writers including Victor Hugo, Balzac and Edgar Allan Poe.

The Birmingham Six were convicted partly on an explosives test that can also react to the coating on which items?

Playing cards are coated with a nitrocellulose polymer, and soaps and lacquers were suggested as other triggers for the test. The six men's convictions were quashed in 1991.

Harry Jackson, the first Briton convicted on fingerprint evidence, left prints in fresh paint while stealing what?

Billiard balls vanished from a house in Denmark Hill, London, in 1902, and the Metropolitan Police's fingerprint bureau matched the windowsill prints to Jackson, a labourer with a burglary record. He got seven years.

Gunshot residue is identified by microscopic particles combining lead, barium and which third metallic element?

Antimony, lead and barium together in one particle are treated as characteristic of gunfire. Labs pick such particles out with a scanning electron microscope fitted with an X-ray detector.

A circuit-board fragment from a bomb timer pointed investigators to Libya after which airliner was destroyed in 1988?

Pan Am Flight 103 fell on the Scottish town of Lockerbie. The fragment was traced to a Swiss firm that supplied timers to the Libyan military, though the firm's owner later disputed the match.

Acid-bath murderer John Haigh was undone when which item of his last victim's survived the acid to be identified?

Her dentures, or part of them, were recognised by her own dentist at the trial. Haigh had wrongly believed that if no bodies could be found, a murder conviction would be impossible.