Using a self-paced moving window reading paradigm, we examine the degree to which structural commitments made while 60 Spanish-English L2 speakers read syntactically ambiguous sentences in their second language (L2) are constrained by the verb's lexical entry about its preferred structural environment (i.e., subcategorization bias). The ambiguity under investigation arises because a noun phrase immediately following a verb can be parsed as either the direct object of the verb 'The CIA director confirmed the rumor when he testified before Congress', or as the subject of an embedded complement 'The CIA director confirmed the rumor could mean a security leak'. In an experiment with 59 monolingual English participants, we replicate the findings reported in the previous literature demonstrating that native speakers are guided by subcategorization bias information during sentence interpretation. In a bilingual experiment, we then show that L2 subcategorization biases influence L2 sentence interpretation. The results indicate that L2 speakers keep track of the relative frequencies of verb-subcategorization alternatives and use this information when building structure in the L2.