In 2002, Zech was elected to the regional council of
Garching an der Alz, where since 2007 worked as a tourism consultant and since 2008 as a fraction chairman of the CSU. In 2009 he was elected as a district chairman of the CSU Garching as well as regional chairman of the Junge Union of Altötting, since 2011 he worked as a regional Chairman of the Junge Union of Upper Bavaria's largest regional association of the Junge Union of Germany. From 2013 until 2017 Zech served as a Member of the German
Bundestag, where he was a full member of the Committee on Employment and Social Affairs and for Economic Cooperation and Development, and a deputy member of the Parliamentary Advisory Council for Sustainable Development. On the Committee on Economic Cooperation and Development, he served as
rapporteur on
China,
Japan,
Kazakhstan,
Kyrgyzstan,
North Korea,
South Korea,
Tajikistan,
Turkmenistan and
Uzbekistan. From 2014, Zech was also a member of the German delegation to the
Parliamentary Assembly of the Council of Europe (PACE), where he served on the Committee on Equality and Non-Discrimination; the Committee on Political Affairs and Democracy; the Committee on Rules of Procedure, Immunities and Institutional Affairs; and the Sub-Committee on the
Middle East and the Arab World. He served as the Assembly's
rapporteur on
Lebanon. Zech returned to the Bundestag in May 2020, when he succeeded
Astrid Freudenstein. In March 2021 Zech became part of a political scandal. On 19 March 2021, he resigned from the Bundestag due to allegations related to Azerbaijan's "
Caviar diplomacy" and for receiving a large sum to campaign for former Macedonian PM
Nikola Gruevski. He continued business relations with that country through cannabis-related company PharmCann Deutschland AG. ==Other activities==