Submissions on enforcement matters (SEMs) allow civil society members to assert that one party to a free trade agreement (FTA) is failing to enforce its domestic environmental laws. Submissions that survive every step of the SEM process result in a ‘factual record’ prepared by a secretariat on enforcement matters. Relying on qualitative comparative analysis and an original dataset compiling the 158 SEMs submitted under the framework of US FTAs, I investigate what conditions make submissions more likely to succeed in leading to a factual record. I find that the existence of previous submissions dealing with the same facts, submissions against developing countries, and the presence of at least one non-governmental organization as a submitter contribute to a submission’s success, but only in conjunction with other conditions and for a limited number of cases. This result provides overall evidence that secretariats’ decisions are unbiased by the factors examined in this paper.