In Germany a 57-year-old trucker was arrested over the weekend. He is accused of shooting over 700 times at trucks (mostly car transporters) and cars over a span of several years. Only few people got injured as this were drive-by shootings on highways and he was aiming at the load, not the drivers. As the case couldn't be resolved for some years it eventually up with German federal police. They used new devices to automatically collect license plate information at central highway locations plus cell tower data from mobile phones to drill down on the suspect.
As soon as the arrest was reported, a discussion about data privacy started in Germany (again). Is it ok to store all the license plate information, even if it was deleted after 10 days? Does a case like this warrant to obtain cell tower information (who had their mobile phone turned on around possible shooting locations and traveling on the highway)? Was it ok to combine the data to find the suspect? There are pros and cons to it and I don't want to comment in either direction. When I teach data management at university I tell my students to be aware of the amount of data they produce, e.g., by having a mobile phone, by traveling, by using the Internet. Such data is stored for billing purposes and for legal reasons (laws that require companies to keep data for 30 or 90 days or even longer). And when there is data, there is always an opportunity to work with it, legally or illegally.
Are you in favor of using such data, maybe within certain limits? Are you always aware of what data you produce? Any opinions or thoughts?