The 'loss of a chance' principle explained

When a solicitor undersettles your claim, the question the court has to answer is: what would have happened if they had done their job properly? Because that involves a hypothetical, the law uses a distinct method known as the loss of a chance.

What "loss of a chance" means

Rather than treating your claim as simply won or lost, the court assesses the value of the opportunity you lost because of the negligence. In broad terms it asks two things:

• Did your original claim have a real and not merely fanciful prospect of a better outcome? This you must show on the balance of probabilities.
• If so, how strong was that prospect? The court expresses this as a percentage and applies it to the value you lost.

This dividing line — proving the negligent conduct on the balance of probabilities, but evaluating the lost outcome as a chance — comes from Allied Maples v Simmons & Simmons.

A simple illustration

The leading cases

Two Supreme Court decisions shape this area:

• Perry v Raleys Solicitors [2019] UKSC 5 confirmed that a claimant must prove they would in fact have brought the lost element of the claim, and that the underlying claim had a real prospect of success.
• Edwards v Hugh James Ford Simey [2019] UKSC 54 addressed how the lost claim should be valued and the limited role of evidence that only came to light later — generally the claim is assessed as it stood when the chance was lost.

Why this is good news for veterans

The loss-of-a-chance approach means you don't have to prove with certainty that you would have recovered more. You need to show the lost opportunity had real value. For undersettled hearing loss claims — where the missing pension and future-loss elements are usually well evidenced — that threshold is often comfortably met.

Working out the percentage and the underlying value is exactly the kind of analysis we carry out as part of your free review.