This multifactorial corpus-based exploration of past tenses focuses specifically on the present perfect (PP) versus simple past (SP) alternation in intermediate-to-advanced learner English produced by French and German native speakers. While existing work on past tenses in L2 has traditionally focused on the role of lexical aspect in the acquisition and uses of these past tenses, the current study focuses on the linguistic context of use of these tenses and identifies the linguistic features whose co-occurrence and combined effects cause native speakers and learners to differ in their uses of past tenses. Methodologically, the study uses a random forests approach including a surrogate logistic regression model and interactions between contextual linguistic features. Overall, the multifactorial results suggest that not all linguistic contexts facilitate native-like uses of the PP and SP equally as some contexts more than others are susceptible to cross-linguistic interference.