For his paper Die Wesensmerkmale der Staatsorganisation in rechtlicher und entwicklungsgeschichtlicher Sicht ("Characteristics of state organization from a juristic and developmental-historical viewpoint"), he was awarded the title of professor in 1964, and taught at the University of Munich until 1966.

[4] As the regional interior minister, he attracted attention when he imposed a levy on nonapproved demonstrations and his proposal for the police to be equipped with rubber-bullet guns.

[4] Already in 1993, Chancellor Helmut Kohl had selected Herzog as candidate for the 1994 presidential election, after his previous choice, the Saxon State Minister of Justice, Steffen Heitmann, had to withdraw because of an uproar about statements he made on the German past, ethnic conflict and the role of women.

[12] In April 1997, Herzog caused a nationwide controversy when, in a speech given at the Hotel Adlon in Berlin, he portrayed Germany as dangerously delaying social and economic changes.

In the speech, he rebuked leaders for legislative gridlock and decried a sense of national "dejection," a "feeling of paralysis" and even an "unbelievable mental depression."

"[13] In November 1998, Herzog's office formally moved to Berlin, becoming the first federal agency to shift from Bonn to the redesignated capital city.

[15] In January–March 2000, with former central bank President Hans Tietmeyer and former federal judge Paul Kirchhof, Herzog led an independent commission to investigate a financing scandal affecting the CDU.

[16] Amid a German debate over the ethics of research in biotechnology and in particular the use of embryos for genetic inquiry and diagnosis, Herzog argued in 2001 that an absolute ban on research on embryonic stem cells – which have the ability to develop into the body's different tissues – would be excessive, stating: "I am not prepared to explain to a child sick with cystic fibrosis, facing death and fighting for breath, the ethical grounds that hinder the science which could save him".

[17] In response to Chancellor Gerhard Schröder's "Agenda 2010" presented in 2003, the then-opposition leader and CDU chair Angela Merkel assigned the task of drafting alternative proposals for social welfare reform to a commission led by Herzog.

The party later approved the Herzog Commission's package of reform proposals, whose recommendations included decoupling health and nursing care premiums from people's earnings and levying a lump monthly sum across the board instead.