Rebuttal: a front-pay figure built on an assumption nobody had tested
The opposing report was arithmetically sound. The number was large because of one unexamined assumption about how long the loss would continue — and that assumption was where the whole figure lived.
Counsel had received a plaintiff-side economic damages report and needed to know whether the figure was defensible, where it was vulnerable, and what the exposure looked like under alternative assumptions — before mediation rather than after.
Reproduce the number first
Rebuild the opposing calculation exactly. If it cannot be reproduced from the stated inputs, that is itself the finding.
Locate where the number lives
Vary each assumption in turn to see which one the total is actually sensitive to. Usually one or two carry almost all the weight.
Test only what is unsupported
Concede what the record supports. Challenge the assumptions that have no support, not the ones that are merely unfavourable.
Present a range, not a rival number
Show the figure under each alternative assumption so the sensitivity is visible, rather than offering a competing single number of equal apparent confidence.
Rebuttal is a different job
An affirmative report builds a number. A rebuttal report finds where someone else’s number actually comes from — which is rarely the part they wrote most about.
Front pay is the usual place. Back pay is largely a matter of record and hard to argue with. Front pay runs forward from trial and rests entirely on assumptions: how long the loss continues, what growth applies, what discount rate is used, and whether mitigation is credited. Change one and the total moves by a multiple.
What we do not do
We do not produce a mirror-image report with every assumption flipped to the other extreme. That is transparent to a jury and it damages the expert offering it.
The stronger position is to accept everything that is properly supported, isolate the one or two assumptions that are not, and show what the number becomes under each alternative — letting the trier of fact see the sensitivity rather than being asked to pick between two advocates.
Exposure understood in time to shape the mediation
Identifying that almost the entire difference between the parties’ figures rested on a single untested assumption about the duration of loss — which reframed the negotiation from arguing about a total to arguing about one input.
Parties, jurisdictions and identifying facts are altered or withheld. Methods, data volumes and outcomes are not.
Recognise your case in this one?
Tell us which part. We will tell you what was actually decisive in it.