In parliamentary committee oversight hearings on fiscal policy, monetary policy and financial stability, where verbal deliberation is the focus, nonverbal communication may be pivotal inNotably, the concern here is with the explanations and justifications aspect of accountability, and as such, the focus is on the deliberative component of accountability, rather than the implications 3 or consequences of any judgements (e.g., sanctions, penalties or other consequences of judgements are not explored in this project). Moreover, the "judgments" of parliamentary committees are not in the form of votes (at least in respect to oversight hearings), but rather are on-going and cumulative assessments of ministers and experts. In this way, both the deliberations and the judgments are dynamic and inherently interactional.Although deliberation is at the heart of decision making within public policy, its contribution remains inherently hard to measure and assess within a systematic framework. One approach to studying deliberation empirically is to apply textual analysis to the verbatim transcripts from committee meetings. In studying American monetary policy decision making, this methodology has proven valuable for gaining insights into both the policy meetings of the Federal Open MarketCommittee and the conduct of oversight by congressional committees. Parliament is especially important for select committee activity, given the much greater prominence of these committees following the key reforms of 2010 which among other things, created the election of committee members and chairs, thereby stripping the power of the party whips to appoint these members and thereby lent the committees greater autonomy in holding the Government to account[6], and even (more rarely) triggering resignations by top officials (most recently, the resignation of a newly appointed Bank of England deputy governor [7]).The findings from textual analysis are instructive as to the depth and breadth of arguments used by policymakers in their defence of policy actions. In particular, this analysis finds that deliberation in fiscal policy hearings contrasts sharply with deliberation in monetary policy and financial stability hearings, and moreover, the deliberation conducted by MPs in the Commons committee also contrasts systematically from that conducted by peers in the Lords committee. The context for these differences in content will be described further below, but the point here is that while textual analysis is effective in empirically measuring the deliberative content, it provides no information as to the delivery of these arguments within a deliberative setting. In short, the written 4 record provides us with the semantic content of deliberation, but not the underlying interpersonal dynamic of the committee hearing. Measuring nonverbal behaviour promises a means to gauge better both the emotive tone of the arguments but also the nature of the intentions of the witnesses appearing before each committee, witnesses whose credibility and inten...