GLOBAL – Detective Sarah Lund is a Luddite. The loner heroine of Denmark’s hit crime drama The Killing is as much of a 70s relic as her Faroe sweaters: She makes notes by hand and shuns modern communication. 

“Check out Sarah’s mobile,” says, Sofie Gråbøl the actress who plays her, “It’s an antique!”

In The Killing, only the bad guys have an iPad, says producer Piv Bernth, while Lund pursues her obsessive investigations with a vintage Scandinavian handset.

“Sofie thinks she makes too many phone calls,” Bernth says, “We’re actually a very low tech show.” 

Gråbøl took issue with the original ending of Series 1 where her character phoned in the identity of the murderer from a kitchen table. She wanted to hijack a car at gunpoint instead. And the script was duly changed.

“You just wanted to fire a gun,” Bernth tells her. “I didn’t actually shoot him though,” Gråbøl replies.

Now she’s back in The Killing Series 2. This time she’s working on a different case, but following on from where the first series left off with shadowy figures recorded on CCTV, crimes filmed and posted on the internet – and police conducting investigations by following convoluted email trails and making, and tracing, endless phone calls. Welcome to modern policing.

Whether Sarah Lund likes it or not, any police officer now attempting to solve a crime will encounter some aspect of mobile phone forensics. 

The Mobile Forensic Lab, Chicago:

The phone rings. It is 1am, and Detective Josh Fazio is asleep. A baby has been abducted. They have the suspects down at the station, but they’re not talking. All they have is a cell phone – can Fazio get the data and find the missing baby?

“There’s not a case we work on now that doesn’t involve a cell phone, a GPS or a video,” says Detective Fazio who set up the mobile devices forensics lab at the Will County Sheriff’s department in Chicago six years ago. That year his team of three investigators dealt with 10 phones. This year he has already processed 900 phones.

“Today 80-90% of every crime involves a digital component – that might be a smartphone, a GPS or another mobile device,” says Rick Mislan, who helped Fazio set up his lab. Mislan is now an academic specializing in Small Scale Digital Device Forensics at Purdue University, and was formerly a Communications Electronic Warfare Officer for the U.S. Army.

Mobile phone forensics has been a growing field in law enforcement since the dawn of the first smartphones, and the immense volume of data has been what Josh Fazio calls a “nightmare” for police and intelligence services.

“We can’t keep up,” Fazio admits. “When we started, we had to buy thousands of different cables because none of the phones were standardized. Now we have to buy less hardware but we have an even bigger problem which is that every handset maker adds individual layers and complexities to each version of the operating software, and has a proprietary file system – making it more difficult for us to access that information.

Fazio is an overworked police officer with 16 years on the force. After working in different divisions including the SWAT team, and eight years as a general investigator, he was frustrated when a case fell apart because the police didn’t have the ability to undertake sophisticated computer forensics: “I started from scratch, I went back to to school and took classes to learn this and set up the lab.”

Now Fazio estimates that he can get all the data needed in 65% of cases. As smartphones have more functions, the police need more tools to access them.

“Five years ago I had one tool, now I have to apply more than five tools to each phone,” he says.

Equipment is expensive, and there are still limitations on what investigators can discover, for example US investigators would be unable to trace a phone with UK numbers.

More and more of us are using smartphones, and they operate as an extension of every aspect of our lives, containing a wealth of information.

“Low level drug pushers used to have these rinky dinky little cell phones, now they are all out on the streets with smartphones,” says Fazio.  

Detectives work with the mobile forensic lab in Will County, Chicago for a wide variety of cases.

“Today we had five phones come in on a narcotics case. The investigators want to know what’s in the phone book, the call log and the text messages,” explains Fazio.

“Then we had two phones come in relating to an indecent solicitation case and for that we’re looking for GPS coordinates, wireless access points and Facebook and Twitter.

“Now we’ve had two more phones in a domestic battery case. We’re looking at text messages for that in terms of possible harassment. And we’ve just had a phone logged in connected to a burglary case.”  

An average smartphone might contain thousands of contacts, hundreds of thousands of text messages, photos, videos and location information. Developers in the military, intelligence agencies and law enforcement are working on new analytic tools which make processing that data easier – but, by and large, it still comes down to an individual investigator looking at, and judging, each piece of information in relation to the case.

“They have to decide what’s important,” Rick Mislan says, “Is it the network of contacts, the inbound and outbound calls, or the timing of those calls?”

Police officers may use that information by sifting backwards to piece together evidence about a crime that has already been committed, but for intelligence agencies the key is to access and interpret information ahead of, for example, a major event like a terrorist attack.

“Technology companies have very valid concerns about customers’ privacy,” Detective Josh Fazio admits. And many civil liberties groups, and ordinary phone users, would rightly demand proper procedures and laws about giving information to government agencies, or the police.

“At the bottom of this though, people’s lives are at stake – and we need help,” Fazio says.

 In the case of the abducted baby, the evidence from the cell phone proved to be crucial. “The suspects had walked into a house and stolen the baby. They had communicated all of this by text message, including where they had left the baby in a local park.

“When we accessed that text message we sent an officer down there straight away – and we rescued the baby before it could come to any more harm.”

The Killing’s Sarah Lund might like to work alone, with only her intuition to guide her and an unfashionable wooly sweater to keep her warm: “She could become Denmark’s Miss Marple,” says Sofie Gråbøl in her character’s defence – but smartphones need smarter investigations, so even heroines in Nordic noir had better get used to it.