The recent December CPR bulletin reported the case of Correia v Williams  EWHC 2824 (KB).
In this case the Claimant's witness statement was inadmissible because it was written in English rather than the witnesses own language, Portuguese; the Claimant was not fluent in English.
The statement had apparently been written from notes taken in English by the Claimant's lawyer. This does not comply with the applicable rules. The practice direction to Part 32 of the CPR, contain very specific provisions as to the requirements that apply when a witness is not fluent in English.
The Court held that the statement was inadmissible and would have required the Court's special permission to be relied upon and such permission was refused. The Appeal Court held that the judge at first instance was entitled to refuse such permission.
On the face of it, this may represent a harsh approach as normally a defect in form will not automatically render a document inadmissible. For instance there are very specific provisions about the format of statements in the practice direction of part 32 and it would seem absurd if these rendered the statement inadmissible, e.g. such as having a 3.5 cm margin (paragraph 19.1 (1)).
However, this decision probably should be seen in the context of the specific provisions in question. This can be seen from paragraph 47, where the judge pointed out the obvious problems that could have ensued at trial if the witness statement had been admitted, namely that during cross examination the witness could simply say that he did not understand a particular paragraph of his statement and meant to say something else.