Attorney Endrik Wilhelm said the siblings, Patrick S. and Susan K., would be filing their historic appeal after a district court in Dresden refused to override a jail sentence Patrick faces. The case, Wilhelm told the daily Dresdner Neueste Nachrichten newspaper, would be to challenge the constitutionality of paragraph 173 of the German Criminal Code, which outlaws sexual relations between close relatives.
The siblings have been in and out of the courts for the past five years. In 2002 Patrick S. was given a suspended sentence of one year in prison for sleeping with his sister. In 2004 he served 10 months in jail for violating the terms of the original conviction, and in 2005 he was sentenced to two-and-a-half years incarceration for incest.
Susan K. never received any jail time since she was always tried as an adolescent. The siblings have four children -- Susan K. has a fifth child from a different father.
The sentence Patrick S. currently faces contains no possibility of parole.
Unusual Family History
Patrick S. and Susan K. are immediate relatives, but they did not grow up as brother and sister. Patrick was adopted and raised by a family in Potsdam, while Susan spent her childhood with their mutual mother in Leipzig.
The two met in May 2000, after Patrick decided to contact his biological family. Their first child was born a year later.
Anti-incest laws have been taken off the books in a number of countries including France, Belgium, the Netherlands, Portugal, Turkey, Japan and Argentina.
Now the Constitutional Court in Karlsruhe will be asked to decide if Germany should follow those nations' lead or if can retain its current legislation.