The judgment of Mrs Justice Hill in Mathieu v Hinds & Anor [2022] EWHC 924 (QB) is interesting for a large number of reasons. Here we look at the judgment in relation to pleading and proving mitigation of loss.

“A defendant proposing to argue for a claimant’s failure to mitigate must give notice well before the hearing by the statements of case or otherwise …and must put forward a “concrete case” to demonstrate what the claimant might reasonably have done.”


The judge was assessing damages in a personal injury case. The claimant was an established and successful artist and the injuries had affected his ability to work.  One of the issues that arose in the case was whether the claimant had mitigated his loss by failing to take up adequate medical treatment.


The judge found that the defendant had raised one issue of mitigation of loss in the counter-schedule. However the defendant did not establish that the claimant had acted unreasonably, it also failed to establish that the steps contended for would have led to a different outcome.  A second allegation of failure to mitigate was rejected on the grounds that it was not proven. Further the second ground was not established by the evidence in any event.

4: Mitigation of loss
4.1: The law and the issues
    1. The well-established general legal principles relating to the mitigation of loss can be summarised as follows:
(i) A claimant must take all reasonable steps to mitigate loss consequent upon the defendant’s breach and will be debarred from claiming “any part of the damage which is due to his neglect to take such steps” (British Westinghouse Electric and Manufacturing Co Ltd v Underground Electric Railways Co of London Ltd (No. 2) [1912] AC 673 at 689, per Viscount Haldane LC).
(ii) In mitigating their loss, a claimant is only required to act reasonably and is not required to do anything outside the ordinary course of events. The standard of reasonableness is not high given that the defendant is an admitted wrongdoer (McGregor on Damages (21st Edition), paragraphs 9-079 and 9-082).
(iii) That said, a claimant must to some degree act with the defendant’s interests in mind as well as their own; and while a claimant might have acted reasonably as far as they are concerned, the issue is whether they have acted reasonably as between themselves and the defendant, in view of the need to mitigate their loss (McGregor, paragraph 9-081 and Darbishire v Warran [1963] 1 WLR 1067, CA, per Harman LJ at p.1072).
(iv) Whether a claimant has mitigated their loss is a question of fact not law (Payzu v Saunders [1919] 2 KB 581, CA).
(v) The defendant bears the burden of proving that it was unreasonable for the claimant to take certain steps in the past or would be so unreasonable in the future (see, for example, Steele v Robert George and Co (1937) Ltd [1942] AC 62 and Sainsburys Supermarkets Ltd v Visa Europe Services LLC [2020] UKSC 24 at [211]).
(vi) A defendant proposing to argue for a claimant’s failure to mitigate must give notice well before the hearing by the statements of case or otherwise (Geest Plc v Lansiquot [2002] 1 WLR 3111 PC at [16]) and must put forward a “concrete case” to demonstrate what the claimant might reasonably have done (Samuels v Benning [2002] EWCA Civ 858 at [26]).
    1. In the context of an alleged failure to mitigate loss by declining medical treatment, the case law suggests that the potential benefits and risks of the treatment in question are relevant. A claimant need not “risk their person too far in the hands of surgeons”, but where the treatment would not be regarded by reasonable people as risky, then a refusal to follow it may well constitute a failure to mitigate (McGregor, paragraph 9-081).
    1. Applying this approach, a claimant was held not have acted unreasonably in refusing treatment in Savage v Wallis [1966] 1 Lloyds Rep 357, CA, where the medical evidence was finely balanced as to whether a slight operation would have cleared up the claimant’s headaches. The same applied in Geest, where no doctor had advised on the prospects of success of an operation or on the risk, however small, that the operation would lead to a worsening of her back pain.
    1. However, individuals who declined medical treatment were found to have failed to mitigate their losses in Marcroft v Scruttons [1954] 1 Lloyds Rep 395, CA, McAuley v London Transport Executive [1957] 2 Lloyds Rep 500, CA, Morgan v T. Wallis Ltd [1974] 1 Lloyds Rep 395, CA and Noble v Owens [2008] EWHC 359 QB Their reasons included an unwillingness to go to a mental hospital (Marcroft) and a “mental block” caused by a genuine fear that was beyond the plaintiff’s control (Morgan). In McAuley the plaintiff had not followed a suggestion made to him by the defendant’s doctor or gone to his own doctor for an opinion (per Jenkins LJ at p.505).
    1. The reasons why a claimant is refusing particular medical treatment also need to be considered. In Edmonds v Lloyds TSB [2004] EWCA Civ 1526, the Court of Appeal, unusually, interfered with a trial judge’s finding that a claimant had acted unreasonably by refusing injections aimed at improving her back pain because the judge had failed to give proper regard to (i) her understandable anxieties about the proposed treatment, especially given that she had been given no guarantees as to its success; (ii) the fact that her GP (whom she trusted) was sceptical that the treatment would be beneficial; (iii) the fact that the doctor who recommended the treatment could give no guarantee as to its success; and (iv) the doctor’s own view that her decision was reasonable.
    1. Co-morbidities which impact on the risks associated with and/or the likely success of the proposed treatment are also relevant. In Stansfield v BBC [2021] EWHC 2638 (QB), Yip J found that it was not unreasonable for the claimant to have refused to take anti-depressants when he had a complex mixture of brain injury and psychological injuries which influenced his decision. Further, the consequence of his taking the drugs and the impact on his losses was not clear: [204] and [206]-[207].
4.2: The issues
    1. In closing submissions, the Second Defendant argued that the Claimant had failed to mitigate his loss by not pursuing (a) treatment aimed at preventing headaches; and (b) further fatigue management sessions.
    1. Mr Dignum argued that there is clear expert evidence that the suggested treatments and therapies are, on the balance of probabilities, likely to be effective in either reducing the Claimant’s headaches or resolving them entirely and improving his fatigue. In the context of a case where the Claimant seeks very high damages for losses based on headaches/fatigue, his failure even to try the suggested interventions is unreasonable and against the body of medical advice and common sense.
    1. Mr Huckle submitted that the mitigation issue had not been properly pleaded and proved. The Claimant has “mastered” his symptoms. The clinical consensus appears to be that he has made a remarkable recovery, such that it is reasonable not to change the Claimant’s approach.
4.3: Treatment aimed at preventing headaches
    1. The Second Defendant argued that the Claimant has not mitigated his loss by taking medication aimed at preventing his headaches, withdrawing from the use of the over-the-counter headache tablets he currently takes or engaging in a postural/relaxation programme.
(a): The evidence
(i): The potential benefits and risks of preventative medication
    1. Dr Orrell and Dr Foster estimated that they had each seen around 20,000 patients suffering from headaches. They agreed that regular use of amitryptiline or a similar drug is a tried and tested preventative medication.
    1. Dr Foster’s view was that if the Claimant took such medication, while stopping the over-the-counter analgesics he is currently using, and perhaps undertaking a postural/relaxation exercise programme, this was “likely substantially to ameliorate [the Claimant’s] headaches to no more than a nuisance level within 3 to 6 months”. He said at trial that the sedative effect of amitryptiline might also help the Claimant’s sleep. Going forward, he thought that if the Claimant’s headaches and sleep improved, then his fatigue would be ameliorated, though the extent to which that would occur is not entirely predictable.
    1. Dr Orrell was less enthusiastic. In his 16 October 2018 report he noted that the preventative medication “may reduce the frequency and severity of the headaches and contribute to resolution”. However, in his May 2021 report he said “The current headaches are described as being deep in his head, and not on the surface. In this respect it is my opinion that medication for prevention of tension or migraine headache, or headache related to skull damage…would be unlikely to be effective”. He carried this view over to the neurologists’ joint statement, recording his view that he considered it unlikely that amitriptyline would relieve the Claimant’s headaches.
    1. Mr Dignum understandably cross-examined Dr Orrell at trial about this apparent “volte face” as to the efficacy of the medication. He agreed that it can be used to treat headaches in the location in the head the Claimant was describing (although he felt the location was unclear). It was apparent that by the time of this report the Claimant had indicated that he did not want to take the medication, but Dr Orrell said that that was not the reason for his comment about the effectiveness of the treatment. I therefore remained unclear as to what Dr Orrell meant in this part of his report. However, he later also said that he was not sure how effective the medication would be on the Claimant’s overall presentation: if it was the fatigue which was so disabling that he had to go to bed, taking the headache out of the equation would not necessarily solve the issue.
    1. Dr Orrell felt that it was likely that a short course of the medication would not work, and that the Claimant would need to take it longer-term. Some patients take it for decades and it was possible he would need to take it for life. Dr Foster estimated there was a 50% likelihood he would not need to take it forever.
    1. Dr Orrell and Dr Foster agreed that a feeling of drowsiness is a well-known side effect of amitryptiline. Dr Orrell said that some people suffer this, some do not. Dr Foster said “many [patients] do not report any sedative effects in the day”; in fact, “the majority don’t”. Dr Foster explained that generally a clinician will introduce amitryptiline very slowly and withdraw it if it is not working. The aim is to ensure that any sedative effect has worn off in the morning. Dr Foster agreed that it is possible to “tinker” with it. In his May 2021 report, Dr Foster noted that amitriptyline was one option but there were a number of others including duloxetine which is “much less sedating”. Dr Orrell agreed that there are alternatives to amitryptiline.
(ii): The potential benefits and risks of continuing with over-the-counter medication
    1. The experts agreed that excessive use of over-the-counter medication puts the patient at risk of the recognised problem of “analgesic overuse headache”, i.e., the painkillers can themselves cause headaches. They disagreed slightly as to the point at which the use of over-the-counter medication would be considered excessive: Dr Foster put the figure at eight to 10, Dr Orrell at 12.
    1. The Claimant had given different accounts of the extent to which he uses over-the-counter medication. In 2016/2018 he had said to Dr Orrell and Dr Gartenberg respectively that he used it two or three times a week. Later he had said he was taking 12 Advil a week. In May 2021, he told Dr Foster in some weeks he was taking 20-30, with eight to 10 in one day.
    1. Dr Foster considered that if the Claimant withdrew from using over-the-counter medication, he could expect a 50% reduction in the totality and severity of his headaches.
(iii): The Claimant’s position
    1. When Dr Orrell first raised the issue of amitriptyline in his 27 August 2016 report, he made clear that it might contribute to fatigue. This is at the heart of the Claimant’s refusal to trial it. He explained in his March 2021 statement and at trial that he was concerned at the risk that amitriptyline or a similar medication would make him feel drowsy and interfere with his creative process: it is “the lethargic state that comes with it” which “I refuse to engage with”. He confirmed he would try medication if there were no side effects but that he did not want to be a “guinea pig”. He said he did not want to “gamble” his health and preferred to deal with his headaches through other means.
    1. Mr Huckle also took me to research indicating significant increases in dementia risks after exposure to anticholinergic antidepressants (of which amitryptiline is one), which highlighted “the importance of reducing exposure to anticholinergic drugs in middle-aged and older people”.[1] He emphasised that the Claimant is already fearful about further loss of cognitive function in the future due to his brain injury, and has brought a provisional damages claim on the basis that his brain injury could lead to dementia.
(iv): The advice the Claimant has received
    1. The Claimant has not discussed the preventative medication option with his treating clinicians. Dr Orrell did not consider it appropriate to advise the Claimant as he was not his treating doctor. Dr Foster and the Claimant had a brief discussion about it and Dr Foster could, understandably, give the Claimant no guarantees that the medication would make the headaches stop. There was some disagreement between them as to whether Dr Foster had said that the medication would, or might, make the Claimant drowsy, but the latteris more likely, especially given Dr Foster’s evidence that in the majority of cases, drowsiness does not occur.
(vi): The experts’ views of the Claimant’s position
    1. Dr Orrell’s impression was that, typically, the Claimant was using over-the-counter medication two to three times a week. This was not excessive, and it would be an escalation of treatment to start taking amitryptiline daily. In those circumstances it was reasonable to treat the headaches as and when they occur, rather than take long-term medication that may have additional long-term effects. Many patients, particularly younger ones, do not want to take medication. As conveyed to him, the Claimant’s regime appeared to be working. However, he also conceded that the medication was “an experiment worth performing” such that it would be reasonable for the Claimant to trial it for three to six months. If it had not had a positive effect by that time, it was unlikely that it was going to.
    1. Dr Foster firmly disagreed that the Claimant’s approach was reasonable. He considered that “plainly” he should seek a treating neurologist’s opinion: “most patients with headaches of that frequency and saying they are impacting on their life as much as he is would seek GP / alternative opinion”. He thought the Claimant had been “unwise” in not acting on the 2016 steer in this regard that he had had from Dr Orrell.
(b): Analysis and conclusion
    1. The Second Defendant had sufficiently pleaded this issue. Although no mitigation argument was advanced in the Defence, the Second Defendant’s Counter-Schedule of Loss took the point.
    1. I found the issue of whether the Second Defendant has discharged the burden of proving that the Claimant has acted unreasonably in refusing to take amitryptiline or a similar medication a finely balanced one.
    1. There is an initial simplicity in the argument that a claimant suffering regular, debilitating headaches is acting unreasonably in declining medication that has a reasonable prospect of preventing those headaches. Further, the evidence suggested that the use of amitryptiline can be carefully titrated, or other comparable drugs used, to reduce the risk of the sedative side-effect, which – on Dr Foster’s evidence – impacts less than 50% of patients in any event.
    1. However, on closer analysis of the facts of this case, the position is more subtle.
    1. This Claimant is a person whose raison d’etre is his art. His ability to produce his art has already been significantly impacted by the combination of headaches, fatigue and cognitive issues. He has made very significant efforts and substantial sacrifices and has achieved a very high level of recovery and function. This has largely been with the aim of ensuring he can maintain as normal an artistic life as possible. In my view there is force in Mr Huckle’s submission that the Claimant has now mediated a way of living with his symptoms, and it is not unreasonable for him to maintain that.
    1. On balance, in my view, it is entirely understandable for him to decline medication which might generate two side-effects of which he is particularly fearful: further drowsiness that is likely to dull his creativity and further cognitive decline in the form of dementia that would be likely to have the same effect. Indeed, from my assessment of him it is hard to imagine two side-effects he would be less willing to tolerate. Given the focus on his art this is an understandable position for him to take.
    1. I am also not satisfied that his use of over-the-counter medication is regularly as high as it was when he gave his account to Dr Foster in May 2021. I accept Dr Orrell’s assessment of the more typical use of this medication by the Claimant. This means that the Claimant is not obviously putting himself at risk of developing analgesic overuse headaches by maintaining his current regime.
    1. It is also relevant that Dr Orrell considers that the Claimant is acting reasonably in this regard. Ultimately it is for the court to decide what is reasonable but the fact that there are two experts with differing views on the issue makes it harder to find that the Claimant is acting unreasonably.
    1. As the determination of whether a claimant has acted reasonably is a question of fact in each case, limited assistance can be drawn from other cases. However, to the extent that comparisons can be made, I consider this case similar to Edwards. Like Ms Edwards, the Claimant has made a careful decision about this issue, his anxieties about it are understandable, he had received no guarantees as to its success and the expert instructed on his behalf considers he is acting reasonably and is sceptical as to the impact the treatment would have on one of his major issues (the fatigue). The case is also comparable to Stansfield to the extent that in both cases there is a complex mixture of brain and psychological injuries which influenced the claimant’s decision.
    1. For all these reasons, I do not consider that the Second Defendant has discharged the burden of proving that the Claimant is acting unreasonably by not taking preventative medication or stopping using over-the-counter medication.
    1. There has been no suggestion that the use of physical/holistic measures alone would be significant under this head: rather, Dr Foster’s evidence only referred to a posture programme “potentially” being used in conjunction with the medication changes.
    1. Further, even if I had found that the Claimant had acted unreasonably in this regard, I do not consider that the Second Defendant has discharged the burden of showing the difference it would have made. True it is that Dr Foster expressed the view that the medication changes would be likely to substantially improve the Claimant’s headaches, but even he accepted that the extent to which this would impact on his sleep and fatigue could not be easily predicted. Dr Orrell was clear that the fatigue would likely remain, and this significantly adversely impacts on the Claimant’s life. In those circumstances I do not consider that the Second Defendant has provided a sufficient evidence base for reducing the Claimant’s losses.
    1. I am therefore not satisfied that the Second Defendant has proved that the Claimant has failed to mitigate his loss in respect of preventative headache treatments.
4.4: Further fatigue management sessions
(a): The evidence
    1. The Claimant has had extensive therapy in Canada: 20 sessions with Dr Gartenberg and a further four sessions with Esther Vahober. These ran from September 2017 to August 2019. In her 26 February 2020 report, Dr Bach recommended that the Claimant have 10-12 further psychological sessions of CBT or Acceptance and Commitment Therapy (ACT), psycho-education and fatigue management. In his report from the same month Dr Nathaniel-James also recommended neuropsychological intervention. The Claimant has not done these further sessions. At trial he said that he did not recall Dr Bach advising him to have more sessions. Thus, it does not appear that he has consciously declined to follow the neuropsychologists’ advice.
    1. Dr Bach’s view as to the efficacy of further neuropsychological input at this stage changed. When she saw the Claimant on 11 March 2021, he said he felt that it was not the right time to start further input and that he wanted to continue working on his adjustment by himself. She felt it was “appropriate for [him] to try and self-manage as this can reinforce his sense of autonomy, efficacy and confidence in the strategies”. She explained in the second joint statement that she felt he was employing CBT and evidence-based cognitive compensatory strategies such that further input would not make any material difference to his fatigue and its impact. I found this explanation from Dr Bach clear and consistent.
    1. At trial Dr Bach was “not at all critical” of the approach to psychological treatment which the Claimant had adopted: it was “perfectly reasonable and acceptable” and he was “already engaged and implementing strategies”. He had been very focussed on his emotional adjustment to the accident and on cognitive strategies to implement and should be commended for the dedicated work he has done in therapy.
    1. The second joint statement recorded that Dr Nathaniel-James was only in “some disagreement” with Dr Bach on this issue. He felt that the Claimant would likely benefit from further CBT fatigue management input at this stage, and at the very least should submit himself for an assessment to ensure he was correctly employing the necessary strategies. At trial, he said he was “not necessarily” critical of the way in which the therapy had been carried out in Canada. He agreed that the Dr Gartenberg sessions had focussed on memory and coping strategies and that the Claimant felt they had been successful which was “as much as you could hope for” as such therapy must to a large extent be patient-led.
(b): Analysis and conclusion
    1. In my view, the Claimant had not been given fair notice of this issue by the Second Defendant. The pleading of the mitigation of loss issue in the Counter-Schedule only referred to treatment for headaches. I do not see how it can properly be read as referring to the issue of further fatigue management. There is no mention of Dr Bach’s recommendation nor any assertion of the likely outcome if the Claimant had complied with it. I therefore consider that the Second Defendant has failed to comply with the pleading requirements set out in Geest and Samuels in respect of this element of the mitigation argument.
    1. In addition, I do not consider that the Second Defendant has discharged the burden of proving that the Claimant has acted unreasonably in this regard. Dr Nathaniel-James’ views about what the Claimant should do at this stage in terms of fatigue management were expressed in a rather “lukewarm” way. Dr Bach was clear that she considers the Claimant has done very well with respect to his psychological input and is acting reasonably with the approach he is taking now. Both experts agreed that this sort of therapy needs to be patient-led.
    1. Finally, the Second Defendant has not advanced any clear evidence of what the impact of any further fatigue management sessions at this stage would be on the Claimant’s loss.
  1. I therefore find that this aspect of the Second Defendant’s case on mitigation of loss also fails.