‘That’s what the internet can do: offer an environment of normality for the sickest and most twisted minds,’ continued Kroeger. ‘The most important thing about the internet is that it gives these people a sense of security, of impunity. And that’s where we come in. There is no such thing as anonymity on the internet. Herr Fabel drew a comparison with real-world investigations: where you can track an offender across an environment, interview eyewitnesses, etc. The truth is that it’s wrong to think the internet is any different. It’s just that it’s a virtual world instead of a physical one. You still leave tracks everywhere you go. And no matter how hard you try to disguise yourself as somebody else, there are always clues to your identity left behind.’
‘How can that be?’ asked Fabel. ‘If someone claims to be a fourteen-year-old girl instead of the forty-year-old man that they really are, how can you see through that?’
‘Okay, let’s start with the basics. A lot of browsers offer private browsing, where nothing is logged in your internet history and your computer doesn’t pick up cookies or other traces of your excursions on the net. The truth is there is no such thing as private browsing. Your internet provider keeps a record of every site, every page you visit. And the administrators of those sites you visit similarly store your IP address. Every time you connect to the internet, you leave a trace. And if you’re dumb enough to use a computer at work or at home, then we’re just one court order away from having your name and address.’
‘But our guy isn’t dumb,’ said Anna.
‘No…’ Kroeger reached into his pocket and produced a USB stick. ‘This is a dongle. This particular type of dongle allows you to access any WiFi spot. Obviously, you still have an IP address, but if you have paid cash for a pay-as-you-go broadband dongle, then your name and address aren’t listed anywhere. My guess is that your Network Killer, if he’s smart, is using one of these. But even if he is, he’s still traceable. Whenever he is online he can’t disguise his location. Or at least he can’t without some pretty sophisticated software. We can identify the general physical location of the connection. If it’s a pay-as-you-go dongle, then he has to top it up somewhere. And that means resurfacing in the real world. The person behind the counter in the newsagent or mobile-phone store who sells him the credits is the witness that Herr Fabel talked about earlier. My point is this. My beat isn’t that dissimilar to yours. There are always tracks left behind, always something to follow. How much effort has been made, and how much skill has been employed in covering up those tracks depends on the intelligence and expertise of the offender. Just like in the real world.’
‘But that still doesn’t answer the question about how to see through a fake identity,’ said Werner.
‘I don’t know how many of you are members of a social networking site, but those of you who are will be aware of the rather disturbing phenomenon of seeing ads for things that are particularly relevant to you, right at the exact time they’re relevant to you… ads for wedding photographers just after you’ve become engaged, a restaurant ad just before an anniversary, sports stores offering you deals in your particular sport… It’s like there’s some kind of cyberpsychic reading your mind. The truth is that you have left so many details of yourself scattered all around. Because you think in terms of normal space, you think that all of these little scraps of information are so scattered that they can’t be put together. They can, and instantaneously. And you’re not even aware of having left some of that information behind: your personal data and browsing behaviour have been analysed, sometimes automatically. Nothing you do is random in the internet. You think it is — you think you jump from one site to another, from one page to another spontaneously, impulsively — but there is always an underlying logic or psychology to everything you do. The truth is that the more relaxed and free-roaming your internet exploration is, the more it reveals about your psychology, your identity. In the Cybercrime Unit we have access to all kinds of experts — IT specialists, sociologists, psychologists, criminologists. We even use linguistic experts who can analyse your vocabulary, your syntax and grammar, and who can profile your educational standards, age, etc. And, as well as the experts, we have analytical software that can give us a breakdown of a user in seconds. So, to answer your question, Herr Meyer: yes, it can be difficult to see through a carefully constructed avatar identity on the web, but we do have an armoury of weapons at our disposal and it’s much more difficult to hide behind an invented identity than you would think.’
‘Thanks,’ said Fabel. ‘Chief Commissar Kroeger will be working alongside us on this and provide the liaison with the other specialists in his unit. Anna has provided him with the full list of possible convergent identities from the social-network sites. What’s narrowed it down is that each of the victims seemed to favour a different site. We’ve found it difficult to find any points of convergence in their day-to-day real lives, and it’s proving tricky in their online activities, but we do know that all four women made regular use of social networking sites to meet men.’
‘One thing I didn’t mention,’ said Kroeger, ‘is that we have a distinct advantage in being in possession of the computers used by each of the women. We have technology that enables us to retrace their steps. We may even be able to recover a good part of their chatroom messages. And that could point us in very specific directions.’
‘Where are we with that?’ asked Fabel.
‘Not that far away. I reckon another day or two and we’ll potentially have a lot of leads from what was keyed into the computers. It’s painstaking work, of course.’
‘Of course,’ said Fabel and smiled. Kroeger was all numbers and no personality. This was no game nor some kind of professional challenge. In two days another woman could be dead. She could be planning to meet her killer right now: chatting, flirting, making arrangements with an electronic fiction of a human being. ‘But, as I’m sure you appreciate, time is of the essence here.’
‘Naturally we will treat this case as an absolute priority.’ When Kroeger spoke he always said the right things. But whatever sentiment was in it never made it into his expression or his grey eyes. He was himself almost a machine, thought Fabel.
Fabel had worked with Kroeger once before, on a child-murder case involving an internet-based paedophile ring; Kroeger had all but come right out and said that he thought Fabel’s technological illiteracy compromised his efficiency as an investigator. But what had riled Fabel most of all was the way Kroeger had remained so detached from the human suffering involved in the case. Kroeger seemed as uninterested in and as uncomprehending of the fact that a child had been murdered and a family ripped apart by horror and grief as Fabel was about the difference between a kilobyte and a gigabyte. The result was a lingering mutual distaste.