A widespread clinical practice can still be negligent. Common errors are nonetheless errors. The Bolam defence only succeeds if a "responsible" body of opinion accepts the practice in question as "proper".
It is therefore not sufficient for a defendant simply to establish that their own practice was one adopted by other healthcare professionals.
In Bradfield-Key v Cope  EWHC 3881 (QB), handed down on 21 May 2020, HHJ Sephton QC, sitting in the High Court, determined liability in a case arising out of a left total hip replacement (THR).
The Claimant had undergone a successful right THR performed privately by Mr Cope, and then consented to a left THR which was performed, privately again, in December 2009. Revision surgery was required in March 2012 and again in May 2016 because of pain caused by the acetabular cup interfering with the iliopsoas tendon.
The Judge dismissed a claim that the Defendant had failed to heed complaints made by the Claimant after the operation, but did find that the surgery had been performed negligently.
The Judge found that the Defendant surgeon had so placed the acetabular cup that the "prominence of the acetabular component was sufficient to cause irritation of the anterior structures, specifically, the left iliopsoas tendon." So the injury was, he found, caused by the manner in which the surgeon had performed the surgery.
Was the technique or practice adopted by the Defendant negligent?
The expert witnesses agreed that "surgeons should ensure the acetabular component is not placed in a position that could interfere with the iliopsoas tendon such as beyond the acetabular margin of the native acetabulum." However, the experience of Mr Manktelow, the Defendant's expert, in particular demonstrated that other surgeons conducted surgery in the same way as the Defendant and failed to ensure that the acetabular component was so placed as to avoid interference with the tendon. The Judge held that the evidence established that "there are other surgeons who appear to adopt the same practice" as the Defendant.
It is worth then following the exact reasoning of HHJ Sephton QC in the light of that evidence:
 Mr Holl-Allen QC [for the Defendant] submits that Mr Maktelow's evidence provides Mr Cope with a Bolam defence and that the claimant is driven to rely upon Bolitho. I do not accept that submission. In my view, both Bolam and Bolitho require the court to examine the different schools of thought and to ask itself whether the school of thought relied upon by the defendant can demonstrate that its exponents' opinion has a logical basis.
 I reach the conclusion that there was no logical basis for neglecting to ensure that the acetabular component was not placed in a position that could interfere with the iliopsoas tendon. No good reason has been advanced for not taking this precaution. It has not been shown that the two views show that there is a nice balancing of different risks about which surgeons could reasonably disagree. The risk of impingement on the iliopsoas tendon was a well-recognised risk which could easily have been identified by visualisation and/or by palpation or running an instrument around the acetabular rim. If there was any risk in the placement of the cup, it was a relatively simple matter to remove the cup and replace it. There was no surgical or anatomical reason for running the risk in this case.
Accordingly the Judge found that the Defendant had performed the surgery negligently, even though he had found that other surgeons adopt the same practice as the Defendant.
Some important points emerge from this judgment:
- A claimant does not have to prove that the defendant's error was unique in order to establish that it was a breach of duty.
- The fact that other healthcare professionals might adopt the same technique or practice as the defendant, does not mean that the practice is considered as "proper" or acceptable.
- The court should always consider whether a body of opinion that apparently condones the practice in question is a "responsible" body of opinion. If the defendant's own expert considers that the body of opinion that shares the defendant's practice is wrong, then the court is surely likely to find that the body of opinion is not "responsible".
- The court should always consider whether the practice that is condoned by a body of opinion is logical or rational. Whilst the courts will pay due regard to professional opinion, judges are the ultimate arbiters of whether a practice is logical or rational.
Saying, "lots of others do the same thing" will therefore not constitute a defence to a clinical negligence claim if what they are doing is unjustified.
I discuss Bolam and Bolitho in more depth in Part Two of Clinical Negligence Made Clear - A Guide for Patients and Professionals.