It is almost always a dispute will develop during litigation as it progresses through the court. The process of producing pleadings, undergoing disclosure and the exchange of factual and expert witness statements will always unveil more about the parties respective position. As a result, it will often be the case that one or both parties need to amend their case to take account of this further information. The general rule is that amendments to statements of case generally should be allowed so that the real dispute between the parties can be heard (Cobbold v Greenwich LBC  EWCA Civ 2074). However,
- It must be possible for any prejudice to the other party to be compensated in costs
- The administration of justice must remain intact.
- Late amendments may not be permitted where the trial date has to be adjourned as a result
- Whether the amendment is permitted will depend on the nature and extent of the amendment. Amendments that significantly expand the scope of a dispute in an ill-defined way are less likely to be permitted.
- In respect of amendments made late, the presumption that the application to amend will be refused.
In CIP Properties (AIPT) Ltd v Galliford Try Infrastructure Ltd, the trial date had been set for January 2016. In April 2015, after disclosure had taken place, the claimant applied for permission to amend its particulars of claim. In particular, it sought to add two new claims to its case. Coulson J dismissed the application. He held that the amendments would make the trial date impossible and hat this was the key reason for refusing the application. Having reviewed the authorities on amendments, he set out four a number of propositions which, it is submitted, correctly summarise the law in this area
- The lateness by which an amendment is produced is a relative concept (Hague Plant). An amendment is late if it could have been advanced earlier, or involves the duplication of cost and effort, or if it requires the resisting party to revisit any of the significant steps in the litigation (such as disclosure or the provision of witness statements and expert's reports) which have been completed by the time of the amendment.
- An amendment can be regarded as 'very late' if permission to amend threatens the trial date (Swain-Mason), even if the application is made some months before the trial is due to start. Parties have a legitimate expectation that trial dates will be met and not adjourned without good reason (Brown).
- The history of the amendment, together with an explanation for its lateness, is a matter for the amending party and is an important factor in the necessary balancing exercise (Brown; Wani). In essence, there must be a good reason for the delay (Brown).
- The particularity and/or clarity of the proposed amendment then has to be considered, because different considerations may well apply to amendments which are not tightly-drawn or focused (Swain Mason; Hague Plant; Wani).
- The prejudice to the resisting parties if the amendments are allowed will incorporate, at one end of the spectrum, the simple fact of being 'mucked around' (Worldwide), to the disruption of and additional pressure on their lawyers in the run-up to trial (Bourke), and the duplication of cost and effort (Hague Plant) at the other. If allowing the amendments would necessitate the adjournment of the trial, that may be an overwhelming reason to refuse the amendments (Swain Mason).
- Prejudice to the amending party if the amendments are not allowed will, obviously, include its inability to advance its amended case, but that is just one factor to be considered (Swain-Mason). Moreover, if that prejudice has come about by the amending party's own conduct, then it is a much less important element of the balancing exercise (Archlane).