This article examines the effects of committee specialization and district characteristics on speech participation by topic and congressional forum. It argues that committee specialization should increase speech participation during legislative debates, while district characteristics should affect the likelihood of speech participation in non-lawmaking forums. To examine these expectations, we analyze over 100,000 speeches delivered in the Chilean Chamber of Deputies between 1990 and 2018. To carry out our topic classification task, we utilize the recently developed state-of-the-art multilingual Transformer model XLM-RoBERTa. Consistent with informational theories, we find that committee specialization is a significant predictor of speech participation in legislative debates. In addition, consistent with theories purporting that legislative speech serves as a vehicle for the electoral connection, we find that district characteristics have a significant effect on speech participation in non-lawmaking forums.