Marcin joined ClientEarth in November 2022. As a lawyer in the Fossil Fuel Infrastructure Programme, he focuses on climate accountability-related litigation and legislation.


Marcin is experienced in the areas of European Union law, international private law as well as international public law, and has appeared many times before the Court of Justice of the EU.

Before joining ClientEarth, Marcin was employed at law firms DZP and CMS, the Polish Constitutional Court and the Polish Ministry of Foreign Affairs.


Marcin graduated summa cum laude from Warsaw University with a Magister degree in law and a Magister degree in economics; ancien pensionnaire étranger of the École Normale Supérieure (rue d’Ulm, Paris).

Marcin is member of the Warsaw Bar Association (OIRP Warszawa) and speaks Polish, English, French, German, Italian, Japanese, Spanish, Russian and rudimentary Silesian.