Dutch police report: traffic data seldom essential

By EDRi · September 22, 2004

Telephone traffic data are only necessary to solve crimes in a minority of
police investigations. Most cases can be solved without access to traffic
data, with the exception of large fraud investigations.

These are the conclusions of a Dutch police report produced at the request
of the Dutch ministry of Justice. The report was recently obtained by the
Dutch civil liberties organisation Bits of Freedom through a public access

The report undermines the Dutch government’s support to the EU draft
framework decision on data retention. The report makes no case for the
proposed data retention as Dutch police already uses traffic data in 90%
of all investigations. The police can already obtain, with a warrant, the
traffic data that telecommunication companies store for their own billing-
and business purposes. The report also shows that the use of traffic data
is a standard tool in police investigations and it not limited to cases of
organised crime or terrorism.

The report is the result of an evaluation of past investigations by the
Dutch police of Rotterdam. Two-thirds of all investigations could have
been solved if no traffic data would have been available at all. The three
main purposes of traffic data in police investigations are: network
analysis (searching for associations of a person to other individuals),
tactical support for surveillance and checking of alibis (through GSM
location data).

Police investigators can compensate a possible lack of traffic data by
other investigative methods such as wiretapping, surveillance, a
preservation order for traffic data and a longer investigative period. The
report states that police officers seldom ask for traffic data older than
six months.

The report was never sent to the Dutch parliament although members of
parliament previously asked for research results about the effectiveness
of mandatory data retention. After Bits of Freedom published the report
new questions have been raised in the Dutch parliament about the reason
for withholding the report.

The use of (historic) traffic data in investigations (April 2003, in Dutch)

(Contribution by Maurice Wessling, EDRI-member Bits of Freedom)