In a reminder of methods used by the East German Stasi secret police, German authorities are collecting human scents to trace activists they believe may try to violently disrupt the G8 summit in June. It's proving highly controversial, and there's no scientific evidence that the method is infallible.
The good thing about living in a country governed by a constitution and the rule of law is that you usually know what to expect. Fritz S. was pretty sure what was going to happen when investigators from the federal prosecutors' office stood on his doorstep at eight o'clock in the morning in Hamburg's St Pauli district.
House search, seizure of files, having his particulars taken down, the 68-year-old left-wing radical had seen it all before. As an anti-nuclear activist he had been investigated a number of times, after attacks on nuclear waste transports, for example. But the visitors who came knocking Wednesday before last wanted something quite different this time -- his smell.
The elderly gentleman had to hold little metal tubes in his hand for several minutes. They were then labelled and sealed. The aim was to determine whether the ageing revolutionary is planning to disrupt the G8 summit in the Baltic resort of Heiligendamm next month, an accusation he denies.
The scent of terror has got Germany's investigators twitching with excitement. So much so that police two weeks ago confiscated a sweaty vest in a store reputed to be part of Berlin's underground scene. The vest seizure was part of an investigation into 21 usual suspects launched by Federal State Prosecutor Monika Harms under criminal law paragraph 129a -- the one about forming a terrorist group.
The sweaty vest was better than nothing. After 14 recent arson attacks by suspected anti-globalisation activists, mainly in Hamburg and Berlin in the run-up to the G8 summit, the investigation has so far produced meagre results. Police are now pinning their hopes on scent comparisons to sniff out who has been writing anonymous letters claiming responsibility for the various attacks.
Why dogs are so much better at smelling than humans.
Shades of East Germany
The Stasi secret police used scent gathering in Communist East Germany, collecting smells in empty jam jars and storing them. The method has reminded Germans of that failed regime of snoopers, and was highlighted in the recent Oscar-winning film "The Lives of Others" about a Stasi surveillance officer.
The domestic policy spokesman for the Social Democrat Party, Dieter Wiefelspütz, finds the new weapon "pretty bizarre." But he knows that unappetising though it may be, the method has been employed by German investigators for a long time.
In legal terms, recording someone's body odour is no different than taking their finger prints. It's covered by the criminal statue book. The scent contains a person's identity just like the lines of his finger tips or his DNA.
Taking someone's DNA is subject to strict conditions but the law permits finger printing and scent recording whenever police deem it necessary as part of a criminal investigation -- which means virtually always. Erhard Denninger, an expert on Germany's justice system, has no problem with scent analysis. "It's harmless by comparison with sledgehammer plans like searching people's computers," he said.
Suspects are told to hold several 10 centimeter steel pipes in succession for several minutes each.
There are strict rules governing this procedure. The interior minister of the state of North Rhine-Westphalia has decreed that "persons must contaminate the metal tubes through their hands", and that the aromatic traces thereby recorded "be secured in glass containers in dry condition."
It sounds harmless. But a number of defence lawyers, Düsseldorf-based Udo Vetter among them, advise their clients not to agree to scent recording. If the state sniffs the sweat of its citizens, it amounts to a "considerable intrusion into one's intimate sphere," he says.
The complexity of collecting someone's scent is the theme of Patrick Süskind's novel "Perfume", recently made into a movie, in which an 18th century murderer wraps beautiful women in cloths which he later boils. Unlike in real life, the perfume specialist chose to kill his victims before taking their scent.
German police officers are a lot more careful with their aroma recording. The little tubes are taken to the police academy in Holte-Stukenbrock in western Germany. That's where Sunny, a Dutch Alsatian, takes over.
Sunny is one of a team of trained supersniffers used by Superintendent Hermann Döpke, 54, to conduct "scent trace comparison."
There is only one other site in Germany where such "scent trace comparison dogs" are used, in the southern city of Stuttgart.
Döpke says the perfect dog is keen to work and has a pronounced predatory nature. The Belgian Alsatian has proved a particularly suitable breed. Only the "best genetic material" is used, he adds.
There aren't many dogs with specialist skills like Sunny or his colleagues Skip and Zoey. "We use the animals' play instinct," says Döpke. Being strict with them is far less successful than praising them or giving them a treat when they get it right.
"We have to get them to remember the genetic scent of a human being," says Döpke. That's the only scent that counts -- not the environmental scent caused by nutrition, soap or pollution.
Even in 19th and early 20th century Germany, villains had to contend with police sniffer dogs. In his 1908 book "Training and Handling the Police Dog", Berlin police chief Robert Gersbach wrote in "Exercise 69: The dog sniffs out a suspect among a number of people" about how a dog's sensitive nose can aid police work.
The dog was given an item of clothing to sniff and promptly found the man in the group who had the same scent. The success ratio was high, but so was the error ratio. After World War II, legal concerns meant that police dogs in West Germany were only used for protection and to find corpses.
East Germans Studied Scent Tracing
It was in East Germany that the idea was revived. The Communist authorites started researching scent analysis in the 1970s. A criminology student at Berlin's Humboldt University earned his doctorate in 1985 with a study on crimefighting "through traces of human scent."
Susanne Boeden experienced first-hand how far the science had progressed under the Communist regime on October 7, 1989 in the Berlin district of Prenzlauer Berg when the then 21-year-old and her 12-year-old sister Marianne were arrested in the early hours of the morning.
Police officers had caught the sisters pasting hand-written fliers to front doors. "Take action against the rigid geriatric government," the fliers said. A naïve, private act of Perestroika.
The guardians of the socialist order saw it somewhat differently: "Violation of Article 220 of the Criminal Code," they wrote in their notebooks, "public vilification of state organs" -- a crime in the former East Germany. "After the police had noted my weight, eye color and other characteristics they brought a preserving jar into the cell, with a yellow cloth inside." Boeden told Spiegel TV in a 1990 interview. "Then I had to press this cloth onto the naked skin around my loins. I knew right then that it was for my body odor."
Boeden's story put the TV reporter on the scent of one of East Germany's best kept secrets: The Ministry for State Security had collected hundreds of thousands of scent samples of critics of the regime. The GDR police preferred cotton cloths, which were used to collect the suspects' smells. The samples were then stored in air-tight containers.
The Stasi stole items of clothing from the regime's opponents at their place of work or where they played sport, or they would take the odor sample from chairs they had sat on in the pub or during an interrogation.
But the Socialist dog lovers refrained from using the scent samples as evidence in court. "It couldnt be scientifically proven which components of human smell allow the dogs to differentiate between them," explains Günter Petraneck, a chemist who helped the East German police track smells for years. This was why "the results of the odor differentiation could only be used as an indicator."
Aromatic Evidence Admitted in Western Courts
But investigators in West Germany felt themselves to be cleverer than their East German counterparts. Olfactory evidence provided by investigators was repeatedly accepted by courts in the Federal Republic. In 1989 a court in Duisburg handed down a long prison sentence to a drunken boatman who had killed a woman while mugging her. Two German Shepherds had picked up the scent of the attacker on the victim's handbag.
And scent has also been used as proof to convict graffiti artists. Yet there has never been an internationally recognized scientific study that proves dogs' infallibility when it comes to odor identification.
Nevertheless, German investigators rely on a strictly defined scent identification procedure, one that has been put to the test thousands of times. Six tubes are placed on a podium, including the sample belonging to the suspect. The dog has to sniff an object that has been handled by someone other than the suspect and then has to find their sample.
In the final test, six samples are laid out, but not the one from the first test. Now the dog has to sniff the real evidence, maybe a tool used for a break in. If three dogs come up with the same results in the preliminary and main tests, then the failure rate is one in every 1.2 million. That at least is what a researcher at the University of Paderborn has calculated.
Sunny, Skip and Zoey have noses that seem to be infallible. The samples are mixed up and even the dog handler doesnt know which one is which.
It seems likely that everyone has different smells. And there is no doubt that dogs have an extremely high sensitivity to smell. But is that enough to label someone as a terrorist? Even in the US, where the rule of law is currently being dismantled in the war on terror, there are qualms about trusting dogs to search for the truth. "Does the Cold Nose Know?" is the title of a critical study by the US academic lawyer Andrew Taslitz, who is demanding that man's four-legged friends be banned from the courtroom altogether.
And scientists meeting at an international conference in Los Angeles in 1999 discussed the issue and decided to distance themselves from the procedure: The error rate was just too high when it came to canine evidence.
Pentagon Funds Research into Terror Scent Detector
In 2003 California's Appeal Court refused to convict Jeffrey Mitchell of murder just because Reilly the sniffer dog seemed to recognize his smell from the bullet casings that were found at the scene of the crime. The court found that there was an "absence of any evidence that every person has a scent so unique that it provides an accurate basis for a scent identification lineup."
Hamburg defense lawyer Gerhard Strate, who has been researching the use of olfactory proof, also finds it hard to believe in the infallibility of animals. "Then we could just replace the judges with dogs wagging their tails."
The scent proof would presumably not stand up in a German higher court -- and such a court would probably hear the case of a terror suspect from Hamburg like Fritz S.
Unperturbed, Ingo Wolf, interior minister in the state of North Rhine-Westphalia, is standing by his dog school. At the beginning of April he even introduced two new specialists to the team: Dr Watson and Dr Quincy -- two bloodhounds. They are supposed to track people on the move. The procedure is called "man trailing," and it was once used in the US to track escaped slaves.
It costs 60,000 to train these kinds of dogs. The intention is to only use Dr Watson and Dr Quincy for good causes: like finding old people who have got lost and confused, or children who have run away. The sniffer dogs orientate themselves by sniffing the dead skin cells that people are constantly shedding, which stick to bushes and trees or fall on the ground.
But this skill is exactly what could make the two new dogs useful for other delicate purposes. For example, if Dr Watson were to get a sniff of the sample taken from the Hamburg suspect Fritz S. then he would be able to find him in a crowd.
Rainer Hamm is a Frankfurt defense lawyer and a former Privacy Protection Commissioner for the state of Hesse, and he warns that "this use of odor samples would be completely unlawful." Investigators have been ordered to destroy suspects' scent samples after the end of criminal proceedings.
But the law doesnt rule out setting up a Stasi-like register of smells. What goes for fingerprints could also apply to smells. Suspects' fingerprints can be kept for years -- in case they are needed again in the future.
Could scent recognition help find bin Laden?
US scientists are currently working on digitally upgrading the controversial dog tests, so that the scents could also be used in the war on terror. The Pentagon is financing research at Darpa -- Defense Advanced Research Projects Agency -- to develop a detector that can pick up the scent of foreign combatants.
The researchers in Philadelphia have already discovered that scent is inseparable from the genetic fingerprint and in particular the immune system. "Every person has their own unique, individual smell," says Gary Beauchamp, the director of the Monell Chemical Senses Center, who is working on the Darpa project.
People carry so much information in their scent it would make every data protector's hair stand on end. Beauchamp is convinced that it should be possible to "recognize how old someone is, what their gender is, and what illnesses they have."
"We need a big leap in technology to create sensors that can do the same thing. But there is a lot of work being done on this now. The time has come for this technology."
The advantage that odor identification has over other kinds of biometric procedures is that the suspect can also be recognized from a distance. And the smell lingers in an area, even if the person is long gone. A caftan worn by Osama Bin Laden, for example, could be enough to betray his location.
In the war on terror, all kinds of unknown possibilities are opening up: Smells that can be digitally traced, can also be digitally saved. Even the conventional register of all Germans could be digitalized and, if needs be, matched to every perspiration in the country.
It will be some time before that happens, but nothing in the law says that the test tubes with samples from people like S. from Hamburg couldnt be stored. As the Stasi have already discovered, subversives' smells dont fade all that quickly.
Reporting by Thomas Darnstädt, Markus Deggerich, Günther Latsch, Cordula Meyer, Andreas Ulrich
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