Since 2009, Linnemann has been serving on the Committee on Labor and Social Affairs, where he is his parliamentary group's rapporteur on welfare payments (Arbeitslosengeld II).

In similar talks following the 2017 federal elections, he was again part of the working group on social affairs, this time led Nahles, Karl-Josef Laumann and Barbara Stamm.

[5] From 2018 to 2021, Linnemann served as deputy chairman of the CDU/CSU parliamentary group under the leadership of successive chairmen Volker Kauder and Ralph Brinkhaus.

Since 2022, Linnemann has been leading a working group – alongside Serap Güler and Mario Voigt – in charge of drafting the CDU’s new party platform.

[9] Ahead of the 2021 national elections, Linnemann endorsed Armin Laschet as the Christian Democrats' joint candidate to succeed Chancellor Angela Merkel.