The next month, he started his independent practice as a lawyer in the law firm "Mayer-Lay und Kollegen" in Überlingen.

[5] Mayer-Lay was an assessor in the local executive committee of the CDU Überlingen from 2005 until 2009, and was press spokesman there from 2009 until 2014.

He has been a member of the state committee on energy, environment and climate protection of the CDU Baden-Württemberg since 2012.

[7] From 2014 to 2019, Mayer-Lay was a city councilor of the large district town of Überlingen and deputy parliamentary group spokesman as well as supervisory board member of Überlingen Marketing und Tourismus GmbH.

[10][11] He has been a member of the State Committee on External Security and Development of the CDU Baden-Württemberg since 2018.

[14] Mayer-Lay was born 1981 in the West German town of Überlingen and is of Roman Catholic denomination.