Customer loyalty cards and crime-fighting

An interesting example of how data gained through the use of a customer loyalty card can be quite problematic for the individual customer can be found at slashdot today:

“Tukwila, Washington firefighter, Philip Scott Lyons found out the hard way that supermarket loyalty cards come with a huge price. Lyons was arrested last August and charged with attempted arson. Police alleged at the time that Lyons tried to set fire to his own house while his wife and children were inside. According to KOMO-TV and the Seattle Times, a major piece of evidence used against Lyons in his arrest was the record of his supermarket purchases that he made with his Safeway Club Card. Police investigators had discovered that his Club Card was used to buy fire starters of the same type used in the arson attempt. For Lyons, the story did have a happy ending. All charges were dropped against him in January 2005 because another person stepped forward saying he or she set the fire and not Lyons.”

What if the person who really committed the arson had not had the decency to step forward? What if the crime in question had been a murder where the actual murderer might face the death penalty if he or she came forward? The above story demonstrates the problem that “objective” traces such as data from customer records are taken to be sufficient when investigating a crime, and that alternatives may then no longer be pursued.

Update: A similar story, albeit not about crime, where a customer loyalty card was used to the clear disadvantage of the owner, can be found here.

On Murder, DNA Profiling, and Policy Windows

A high profile murder case in Germany has led to a growing debate about easing restrictions on DNA profiling.

Last week, flamboyant fashion designer Rudolph Moshammer (his private website is offline at the moment, but you can find some pictures and a German language report here and an English language summary here) was found murdered in his villa in Munich. Moshammer being a major local celebrity, this spawned a big police operation -- and only two days later, a suspect was arrested.

According to police reports at a press conference, the quick identification of the suspect was possible through the use of DNA profiling: DNA found at the crime scene was analysed and a query in the German Federal Bureau of Investigation DNA database threw up a name. The suspect was quickly arrested and confessed to the murder after a night of interrogation.

This quick success has now led to an intense debate about increasing the use of DNA profiling in law enforcement. Politicians from both big German parties (CDU/CSU and SPD) have called for an extension of the use of DNA samples in police identification of suspects, and an easing of the present restrictions on them (see examples here and here, both in German).

A couple of quick observations on this:

• It seems a classical case of non sequitur to ask for an extension of DNA profiling when the case at hand has proven that the present state of affairs is sufficient.
• Interestingly, this topic divides both the government and opposition political "camps", for both the Green Party (coalition partner of the Social Democrats) and the Liberals (potential coalition partner of the opposition Christian Democrats) oppose such an extension.
• John Kingdon (in his classical work on "Agendas, Alternatives, and Public Policies", 2nd ed. 1995) used the notion of a "policy window" which seems useful to understand the present debate. Let me quote: "An open policy window is an opportunity for advocates to push their pet solutions or to push attention to their special problems. Indeed, advocates in and around government keep their proposals and their solutions at hand, waiting for an opportunity to occur." (p. 203)

It would seem that the Moshammer murder is just such an opportunity for those who want to push for more use of DNA profiling in Germany -- politicians of various persuasions and the police. Already the state of Bavaria has announced that it will propose a bill for the more widespread use of DNA profiling in law enforcement in Germany. According to the Minister President "DNA analysis has to become the fingerprint of the 21st century". Let's see how long the policy window stays open and whether this initiative will succeed.