A February order by a German Federal Constitutional Court determined that it is legal in Germany for telecommunications companies to demand formal identification from customers setting up prepaid SIM cards, but a regional Pirate Party politician appealed that ruling earlier this week.

Patrick Breyer, a member of northern Germany's Schleswig-Holstein regional parliament, and his brother Jonas Breyer, a lawyer, appealed to the European Court of Human Rights in Strasbourg. The appeal says that anonymous communication is protected under the European Convention on Human Rights' right to private life.

Denmark and France have outlawed anonymously purchased prepaid cards, but the Breyer brothers asserted that Germany's similar law is pointless because identification can be falsified, or people can bring prepaid phones in from other countries.

While German authorities claim the law prevents illegal activities, members of Germany's digital privacy-conscious Pirate Party disagree. "Germany's Breyer said in a statement that anonymous phone calls were important for a range of legitimate activities, from protecting journalistic sources to confidential business dealings," Reuters reported.

Freedom of private communication has been a hot-button issue lately, with an appeals court saying earlier this week that police could track a drug dealer's phone without a warrant by pinging the phone's GPS chip. And an app called "Burner" was released the week before, allowing users to create temporary numbers so the recipient of the call can't track the caller back.