He represented the CDU on several parliamentary committees, including the one on budgets, European affairs, environment and culture.

In addition, he was a member of the Special Committee on Administrative Reform and two subcommittees, as well as finance areas and public companies.

In 2007, Kruse was appointed to the City of Hamburg's Council on Climate Protection by Mayor Ole von Beust.

[2] Kruse was selected to contest the constituency of Hamburg-Eimsbüttel, which the CDU had never won and which the Social Democratic Party of Germany (SPD) had held since the 1950s.

[6] In the negotiations to form a coalition government under the leadership of Chancellor Angela Merkel following the 2017 federal elections, Kruse was part of the working group on economic policy, led Thomas Strobl, Alexander Dobrindt and Brigitte Zypries.

[7] In June 2017, Kruse voted against his parliamentary group's majority and in favor of Germany's introduction of same-sex marriage.