Jahn was a politician and a Social Democratic (SPD) loyalist to his fingertips and he served instead as one of the three Geschaftsfuhrer (parliamentary whips) of the parliamentary SPD until his retirement in 1990, a post he had previously held before taking office.
Jahn was born, in 1927, the son of a medical practitioner whose practice was in a working-class housing settlement on the outskirts of Kassel. He attended a Humanist Gymnasium (grammar school) before being caught up in the war. Aged 15, he was conscripted as an airforce auxiliary manning anti-aircraft guns in 1943-44, before being sent to the Reich Labour Service. At the end of hostilities he found a job in the food office of the local town hall. In 1947 he gained his matriculation certificate and enrolled at the University of Marburg as a law student. To support himself he worked at various jobs including playing in a dance band before being engaged by the Marburg SPD as a secretary/organiser.
Thus began his long political career in the party. He was elected leader of the SDS - the student movement of the SPD - at Marburg University where he graduated. Jahn qualified as a lawyer in 1956 and opened a law practice. His election to the Bundestag followed in 1957 and he remained a member until 1990.
In his second election campaign, 1961, he created a minor sensation by being directly elected, instead of over the SPD list for the district, for the Marburg consituency. This was a surprise as it was largely made up of the small university town and the surrounding agricultural area. It was typical Christian Democratic, rather than SPD, territory. His success was believed to be due to his thoroughness in getting to know local bodies including the town football club.
As a member of the Bundestag Jahn served on a variety of parliamentary committees which gave him insights into the key areas of policy. Promotion came in 1960 when he was elected to chair the committee on restitution in the public service. His predecessor, Alfred Frenzel, had been exposed as a spy for the Soviet KGB. He spoke for the SPD in the complicated and controversial debates over the proposed emergency powers legislation in the mid-1960s. He represented the SPD in several legal cases and became known for his ice-cold precise inquisitorial questioning.
His only setback was when the police discovered a defence committee document he had passed to a journalist revealing that the Defence Minister, Franz Josef Strauss, had committed perjury during the so-called Spiegel Affair. He resigned as SPD Geschaftfuhrer only to be re-elected unanimously when the action was vindicated by events.
During the "grand coalition" of Christian Democrats and the SPD Jahn served as Parliamentary State Secretary to the Foreign Minister and Deputy Chancellor, Willy Brandt, 1967-69. When Brandt took over as Chancellor in 1969 leading the SPD-Free Democratic coalition, he selected Jahn as Minister of Justice. Jahn's wide-ranging committee work now stood him in good stead as all proposed laws landed on his desk. He embarked enthusiastically on a long-thought-out reform programme.
After both left office Jahn remained friends with Brandt. As SPD chairman Brandt asked Jahn to go to Madrid in 1975. The young leader of the underground Socialist Party and future Prime Minister, Felipe Gonzalez, was being prosecuted for "subversive activities". Jahn was to act as observer. The trial was subsequently stopped and then abandoned. From 1975 to 1977 and again from 1979 to 1982 Jahn served as West German representative to the UN Human Rights Commission.
Gerhard Jahn, politician: born Kassel, Germany 10 September 1927; married first Anna Waas (two sons, one daughter; marriage dissolved), second Ursula Muller; died Marburg, Germany 21 October 1998.