Rival camps agree on which facts the decision needs and commission the answers together from sources both trust, so the argument moves from whose numbers to what the numbers mean.
An example
An auto parts manufacturer was deciding whether to switch to a cheaper supplier for a brake component. Sales feared warranty claims would rise; purchasing said the new part met every specification. Each side had its own figures, and two meetings had ended in a fight over whose were right. The director of quality engineering proposed that the two sides agree on the questions that mattered and have them answered by sources both trusted. They settled on three: failure rates in accelerated life testing, the supplier's defect rate at two other customers, and the cost of a recall at the new failure rate. The company's test lab and an outside test house ran the life tests side by side. The results showed a small rise in failures, within warranty reserves. Sales accepted the numbers, and the switch went ahead with a monitoring clause in the contract.
Why it works
Disputes in which each side brings its own numbers rarely end, because each distrusts the other's data and the argument becomes about whose figures are right. Agreeing which facts matter and commissioning the answers together from trusted sources makes the outcome easier to accept, since both sides own the facts. A proposal the joint facts support looks better, and the argument shifts to what the numbers mean. Both parties have to commit to the questions and sources in advance, and the sources have to be ones both trust. A sponsor who expects to lose on the facts will resist it.
The thinking behind it
Lawrence Susskind The Consensus Building Handbook: A Comprehensive Guide to Reaching Agreement (1999), edited by Susskind and colleagues, includes a chapter on joint fact-finding: stakeholders with differing interests develop data and build common assumptions together, then use the shared information to decide. Because the parties agree on the experts and the questions, the analysis cannot become a contest between each side's own figures, which is what had stalled the supplier decision.
Roger Fisher Getting to Yes: Negotiating Agreement Without Giving In (1981) advises insisting on objective criteria, a basis independent of either side's will, searched for jointly, with each side yielding to principle and never to pressure. Life tests run side by side by the company's lab and an outside test house gave such a basis, and sales could accept the result without appearing to give in to purchasing.
When it fits
Disputes driven by competing data are its ground: warranty costs, market size, safety performance, the cost of a change. Both sides must be willing to agree on questions and on sources they both trust, and someone must find the budget and time to commission the work. It suits a sponsor confident the facts favor them, or willing to accept them either way.
How to use it well
Raise it once the argument has become a fight over numbers, and frame it as a way to settle the facts so the decision can be made.
- Agree the questions first: which facts would change the decision.
- Agree the sources and the method together, before anyone sees results.
- Have both sides present when the work is done, or do it jointly.
- Agree in advance how the results will be used.
Be prepared to accept results that go against you. The method's value lies in its fairness, and a sponsor who rejects the facts after agreeing to the process loses credibility for every argument after it.
What it costs and where it backfires
Joint work takes time and money and delays the decision. The facts may go against you, and having agreed to the process, you will have to accept them. Commissioning facts jointly also shows the weak spots in your own data. The method stays clean while both sides genuinely choose the questions and sources. Steering the inquiry to a source you know will give your answer is commissioned validation, and once discovered it ends the trust.
When it is used on you
Take part fully when a rival proposes joint fact-finding. Insist on the questions that matter to you and on sources you trust, and agree in writing how the results will be used. Then accept the results, or name exactly where the method failed before anyone knows what they show.