Trends towards participatory and deliberative methods of science communication have led to recommendations for best practices. Research about good deliberative public engagement in theory has suggested areas of consensus.

In practice, some areas of supposed consensus require tradeoffs. Other researchers have discussed five tensions in STS public engagement; I focus on three as tradeoffs. The tradeoffs are representative or inclusive participation; public or organisational ownership; and upstream or actionable outcomes.

Case studies of deliberative public engagement with science in Australia will be used to discuss how these tradeoffs happen in practice. Specifically examples of deliberative polling and citizen jury methods, about genomics, synthetic biology and nuclear waste.

Information in deliberative public engagement with science will also be discussed. What information is deemed relevant in design phases reveals organisational norms. Choices such as which scientists present or which expert witnesses are available for participants to engage with are made in design stages.

However communicative actions of participants during processes can change what information participants use to develop mutual understandings. For example, live voting during a process, or people sharing personal narratives, provide extra information that may be used in decisionmaking.

Tradeoffs in deliberative public engagement with science is for researchers and practitioners interested designing or supporting public engagement processes.