Do deadlines help a group reach consensus? Or do they get in the way? Yesterday brought the news that the latest round of talks in the peace process in Northern Ireland had broke up without agreement, the deadline having passed. There's a report from the BBC here.

I make no comment on the content of the talks, but I am interested in the process. Why was this particular deadline set? And do deadlines help by providing a sense of jeopardy - a time when the Best Alternative to a Negotiated Agreement comes into play? Or by restricting the time for exploration and low-anxiety creativity, do they get in the way of positive consensus?

Deadlines for discussion and agreement may be tied to objective events in the real world: mother and midwife need to agree how to manage labour before it happens. They may be tied to objective but less predictable events: the Environment Agency and the stakeholders discussing details of the Medmerry Managed realignment flood defence scheme wanted to get it built in time to protect the area from the higher risk of winter storms and flooding. Or they may be tied to other events which are choices rather than unstoppable events, but ones where choosing not to meet the deadline would have very large consequences: the Environment Agency and the Olympic Delivery Authority needed to agree how to handle drainage and water quality from the Stratford Olympic site in time for the games to happen in 2012.

I may be missing something, but the Haass talks don't seem to have any of these justifiable external pressures. So why the deadline?