This corpus-based study investigated verbal interruptions during parliamentary interpellations based on official and publicly accessible transcriptions provided by the Legislative Yuan of the Republic of China (Taiwan). While interruptions have previously been understood as organizing turn-taking, as well as cues and speech markers, the results of this study suggest that interruptions have a dual nature. Interruption is incentivised by confrontational discourse strategies and realized by linguistic expressions, some of which are statistically significant and can be called keywords. Using open-source data to explore the linguistic features in the speech patterns of interruptions in institutional discourse, we first identified the word classes and keywords with significant frequency shifts between interrupted, interrupting, and regular sentences. Then, we associated the meanings of the keywords with offensive and defensive discourse strategies. The findings of this study indicate that interrupted sentences were more reflective of defensive discourse strategies, while interrupting sentences were associated with offensive ones. Moreover, conjunctions, adverbs, and pronouns played a more important role in the speech patterns of interruptions compared with their respective footprint in the lexicon. Conversely, nouns and verbs, with some exceptions, as well as adjectives, played a lesser role. We argue that the confrontational incentive structure in institutional debates creates certain linguistic patterns, mostly statistically significant frequency shifts of keywords in interrupted and interrupting sentences, and that these patterns might be useful in explaining interruption.