BackgroundIn 2012, the UK Government consulted on standardised packaging (SP) of tobacco products. Four transnational tobacco companies (TTCs) submitted large responses opposing SP, criticising evidence cited and citing alternative evidence to support their case. We examine the problems faced by policy makers assessing large volumes of diverse evidence submitted by well-resourced corporate interests to public consultations, and discuss potential strategies for evidence management in public health policy making. MethodsWe synthesise the results of three UK-based studies. Data were identified from four TTC submissions (available online). Assessment criteria for content analyses were developed by literature review. Independent second coding of data was used to validate findings (studies 1 and 2: 100%; study 3: 13%), examine convergence, and resolve interpretation differences. Study 1 was a comparative content analysis of quality (independence, peer-review) and relevance (subject matter) of 77 research documents cited by TTCs to argue that SP will not work, and 37 research documents from a systematic review (SR) of SP. Two-tailed Fisher's tests were used to compare datasets. Study 2 was a content analysis of quality, relevance, and type (eg, research, opinion, policy) of 92 documents and quotations cited by TTCs to argue that SP will have negative, unintended consequences for the UK economy and illicit trade. Study 3 was a qualitative interpretive analysis of techniques used by two TTCs to undermine evidence of SP's effect on smoking behaviour. 120 purposively selected pages (of 1037) were analysed using a verification-oriented cross-documentary analysis, comparing use of research with originals, and a thematic analysis, informed by principles and techniques of constructivist grounded theory—conceptual coding for a-priori and emergent themes, constant comparison, discourse sensitivity, and attention to divergent data. FindingsIn 1521 pages, the four TTCs cited 143 formal research documents to underpin their opposition to SP and made extensive reference to policy documents, quotations, and media coverage. In study 1, 12% of TTC research evidence that SP will not work was both relevant (addressed SP or tobacco packaging) and fulfilled one or more quality criteria (independent of TTCs, published in a peer-reviewed journal, or both), compared with 100% of SR evidence. In study 2, 16% of data were both independent and relevant. TTCs offset the scarcity of outcome-based evidence on the consequences of SP with industry-commissioned research and used independent and industry-connected opinion to inflate the risk of unintended consequences. In study 3, TTCs misused published evidence through inaccurate reporting, attempted methodological deconstruction through mimicked scientific critique, and sought to promote a parallel evidence base to reduce the power and credibility of evidence supportive of SP. InterpretationTTCs used sophisticated, complex, and mutually reinforcing evidential presentation strategies to oppose SP. Assessment of submissions and associated evidence represents a substantial challenge and cost, causing delay or even abandonment of policies. Two strategies could address this. First, implement evidential management processes at submission (eg, requiring respondents to record evidential funding sources, conflicts of interests, and accuracy of evidential representation). Second, introduce a formal post-submission evidence assessment framework. Such strategies could reduce costs imposed on policy makers by the present requirement to invite and assess evidence from stakeholders. They might also reduce the ability of corporate interests to use evidence misrepresentation to oppose policy change. The resource advantage of TTCs is a substantial challenge to potential reforms. FundingJLH and KAE-R are supported by Cancer Research UK (CR-UK; grants C38058/A15664, C27260/A12294). SU, GJF, and ABG are supported by the US National Cancer Institute (R01CA160695). All authors are members of the UK Centre for Tobacco and Alcohol Studies, a UK Centre for Public Health Excellence (MR/K023195/1) funded by the BHF, CR-UK, ESRC, MRC, and NIHR, under the auspices of the UK Clinical Research Collaboration. The content is solely the responsibility of the authors and does not necessarily represent the official views of the funders.