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Causation of Loss, and the 'but for' Principle Explained

Man in suit with outstretched hand, as if to offer to shake. Other hand is resting on open book on a table.

This article was written by Paul Turner – Partner and Specialist CRPS & Fibromyalgia Personal Injury Lawyer at FT Chronic Pain Solicitors.

One of the most difficult principles relating to personal injury claims for my clients to understand is causation of loss and damage.

My clients often ask me, why they are being scrutinised by defendants, why they are made to feel like frauds and why they have to give over personal data like their full medical records from birth. I understand this seems hugely invasive. Why should medical events 20 years prior to someone being injured have any relevance whatsoever to an injury claim? I shall try and explain.

When we talk about causation, in the legal sense, we are talking about the ‘but for’ principle i.e. but for the accident would the claimant be in the same, better or worse position. I'll give you some examples to make this clear a bit later on.

When you suffer an injury as a result of another and the Defendant admits ‘primary liability’, that means they admit their breach of statutory duty or negligence resulted in the injury.

An admission of primary liability does not mean the defendant admits the extent and nature of the injuries, this is very much for each Claimant to prove and often the point Defendants will determinedly try to disprove.

A straightforward example of a causation argument which is common in personal injury litigation is where someone who prior to an accident is fit and well and has no health issues, goes on to develop neck pain following an accident and that pain doesn’t go away as expected. Naturally, the person who has suffered the injury will assume all of the pain was caused by the accident. Anyway, during the course of investigation of the claim, the injured party may have to undergo a scan to identify any physical cause of pain like a fracture or a lesion, so as to enable understanding about what treatment or surgery may be beneficial. The reason for the scan is also to rule out or confirm any underlying degenerative changes that may be associated with the pain i.e. an alternative cause of pain.

Typically, clients will say, “but I had no pain before the accident” and it’s hard for them to imagine that ‘but for’ the accident, they may have had pain at some point in any event because of an underlying asymptomatic degenerative condition.

Why this is important can be pertinent if someone has a protracted period off from work. The extent of recoverability of lost income hangs very much on the medical opinion of the ‘but for’ position. Inevitably the defendants will try to argue that if the accident hadn’t happened the claimant would be in the same position, i.e. they would have neck pain anyway. If the defendant establishes this argument, any long-term financial losses claim would fail. A Claimant is required to prove their claim and so must provide evidence that ‘but for’ the accident, they would not have had pain either at all or for many years.

The battleground in such a case often turns on whether an accident has accelerated the natural pathology in a person’s neck so as to bring forward the pain they would have had in the future in any event. This is known as the acceleration period. If medical experts agree the acceleration period is five years, this would easily enable valuation of both the injury and financial losses capped at five years. Inevitably the Defendants will contest the length of the acceleration period to reduce their liability.

In chronic pain cases, causation is a fierce battleground which can go on for many years, often being disputed right until the point the case settles. What it comes down to is the strength of medical evidence, witness evidence a person’s medical history prior to and following the accident any surveillance evidence and any other relevant records.

The reason causation is such a fierce battleground in chronic pain cases is because by their nature these claims tend to be very high value and therefore from a financial perspective there is plenty to fight for.

Often chronic pain conditions are invisible - such as Fibromyalgia - and this makes it very difficult to prove by way of objective evidence that someone is experiencing pain. When someone breaks their leg, it’s easy to see objectively bot from X-Rays and the cast that they are injured, but this is not the case with many chronic pain complaints. How can you tell if someone is in pain or not? You might think it would be obvious by their movements, screaming out in pain or a grimace perhaps.

Often people living with chronic pain will mask the extent of their suffering on a daily basis so as to avoid alienating themselves from family and friends. People don't tend to want to moan and groan about their pain all of the time and they will often become quite good at pretending to be ‘normal’ because that is who they want to be.

In such cases we often encounter surveillance evidence which will be used to disprove someone’s pain. This is where one or more surveillance operatives observe a claimant from afar over a series of days. Defendants will try and use this evidence to argue that an individual is in it for financial gain and that they are malingering.

Surveillance will attempt to show a claimant functioning normally from day-today, but won’t show the after-effects of that normal function, which may be days of suffering a flare up, fatigue requiring bed rest. This is where strong witness evidence comes into play and we work hard to ensure our client’s have high quality witness evidence prepared which paints a full picture of them prior to and following the accident often drawing on loved ones to give their view of the extent of the problems being experienced.

As part of the claim’s process the claimant will obtain medical evidence usually from a consultant orthopaedic surgeon, a pain consultant and a psychiatric expert. Their job is to consider the Claimant’s pre and post-accident medical records in order to unearth any relevant history such as prior widespread musculoskeletal pain, any social or domestic issues which would predispose them psychologically to developing a chronic pain condition and where there is a future loss claim whether any other health issues might have resulted in them being off from work and requiring care anyway. Experts must also carry out an examination on the Claimant and give their professional view on things like objective signs if any, range of movement at examination.

The defendant experts will attempt to scrutinise clinical records post-accident to draw out any inconsistencies in things like range of movement and levels of pain. They’ll even scrutinise DWP records to check consistent complaints about things a claimant claims not to be able to do in an attempt to secure benefits to replace lost earnings after an injury.

When we take on a new chronic pain case, one of the first things we do is scrutinise the client’s medical records ourselves so as to understand whether there are any ‘red flags’ in their history which the Defendant’s might use to argue the causative basis of the claim. We carry out this forensic exercise and by doing so at an early stage can give advice on the merits of a claim early on.

Causation is a huge subject and it is very difficult (without talking for a long time) to give you real insight to the issues, but hopefully this will have given you a little more understanding of what causation is and why it is so important in the context of personal injury litigation.

Contact FT Chronic Pain Solicitors today

FT Chronic Pain Solicitors is a law firm dedicated to representing those who suffer from chronic pain as a result of an accident that was the fault of someone else. Our two partners, Anne Felmingham and Paul Turner, have decades of experience in this area of the law, and have over the years, recovered millions of pounds in damages for their clients. We offer sound legal advice, but also work at facilitating information, treatment, and support for those we represent.

If you suffer from chronic pain caused by the negligence of others, we would be happy to offer a free initial consultation. We are a modern law firm which is not constrained by bricks and mortar, so we prefer electronic communication in relation to documents. Contact us today by email, or give us a call to see how we can help you with your personal injury claim.


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