The court may, at any stage of the proceedings, on application by any party or of its own motion, order that any document in the proceedings be amended, or that any party have leave to amend any document in the proceedings, in either case, in such manner as the court thinks fit: CPA s 64. Such amendment may have the effect of adding or subtracting a cause of action which has arisen after the commencement of the proceedings or correcting a mistake in the name of a party (s 64(3), (4)), but the section does not apply to the amendment of a judgment, order or certificate: s 64(5).

Subject to the dictates of justice described in s 58 of the CPA, all necessary amendments shall be made for the purpose of determining the real questions raised by, or otherwise depending upon, the proceedings, correcting any defect or error in the proceedings and avoiding multiplicity of proceedings: s 64(2).

Prior to the High Court’s decision in Aon Risk Services Australia Ltd v Australian National University (2009) 239 CLR 175 (Aon), the common law position was that case management was not an end in itself, but an important and useful aid for ensuring the prompt and efficient disposal of litigation: State of Queensland v JL Holdings Pty Ltd (1997) 189 CLR 146 at 154. However Aon disapproved JL Holdings, which predated the statutory enactment of principles of case management: at [6], [30]; [93], [111].See also Dennis v Australian Broadcasting Corporation [2008] NSWCA 37 at [28]–[29]. Prior to the enactment of case management principles, it was more readily assumed that an order for costs occasioned by the amendment would overcome the injustice to the amending party’s opponent: Cropper v Smith (1884) 26 Ch D 700.

In Aon at [96], the plurality held that the approach taken by the plurality in JL Holdings proceeded upon an assumption that a party should be permitted to amend to raise an arguable issue subject to the payment of costs occasioned by the amendment. So stated, it suggested that a party has something approaching a right to an amendment. The plurality in Aon held that is not the case. The “right” spoken of in Cropper v Smith needs to be understood in the context of that case and the case management rule, which required amendment to permit the determination of a matter already in issue. It is more accurate to say that parties have the right to invoke the jurisdiction and the powers of the court in order to seek a resolution of their dispute. Subject to any rights to amend without leave given to the parties by the rules of court, the question of further amendment of a party’s claim is dependent upon the exercise of the court’s discretionary power: at [96]. The reference in r 21 of the Court Procedures Rules 2006 (ACT) to the need to minimise costs implies that an order for costs may not always provide sufficient compensation and therefore achieve a just resolution. It cannot therefore be said that a just resolution requires that a party be permitted to raise any arguable case at any point in the proceedings, on payment of costs: at [98].

A plaintiff may make one amendment to a statement of claim within 28 days after the date on which the statement of claim was filed, but not after a date has been fixed for trial (subject to the power of the court to otherwise order). The defendant may amend his or her defence within 14 days after service of the amended statement of claim (UCPR, r 19.1); but the court may disallow any such amendment: r 19.2.

An amendment to a pleading will be refused if a party has deliberately framed his case a particular way and the opponent may have conducted his case differently had the new issues been previously raised: Burnham v City of Mordialloc [1956] VLR 239; Harvey v John Fairfax Publications Pty Ltd [2005] NSWCA 255. In particular, a late application to add a limitation defence may be refused if the parties have, until that stage, fought the case on other grounds: Ketteman v Hansel Properties Ltd [1987] 1 AC 189.

Other matters which may result in refusal of the amendment include:

An amendment to the originating process so as to claim pre-judgment interest should normally be allowed: Heath v Goodwin, above.

If there emerges at the conclusion of the evidence facts which, if accepted, establish a cause of action factually different from the cause of action which the plaintiff has sued upon, then such issue must be considered by the tribunal of fact and the pleadings should be amended in order to make the facts alleged and the particulars precisely conform to the evidence which has emerged: Leotta v Public Transport Commission of NSW (1976) 50 ALJR 666 at 668. In the case of particulars, amendment, although desirable, is not essential: Dare v Pulham (1982) 148 CLR 658 at 664.

As a general rule, an amendment, duly made, takes effect, not from the date when the amendment is made, but from the date of the original document which it amends. Formerly, an originating process (statement of claim or summons) could not be amended so as to add or substitute a new cause of action which did not exist at the date of the commencement of the proceedings: Baldry v Jackson [1976] 2 NSWLR 415 at 419.

Section 64(3) of the CPA now expressly authorises an amendment to an originating process which adds or substitutes a cause of action arising after the commencement of the proceedings and provides that, in such cases, the date of commencement of the proceedings is to be taken to be the date on which amendment is made.

Section 64(4) authorises an amendment if there has been a mistake in the name of a party. In such a case, the amendment takes effect from the date of the original document which it amends: East West Airlines Ltd v Turner (2010) 78 NSWLR 1.

UCPR r 19.2(4) provides that if a person is added as a party under that rule, the date of commencement of proceedings in relation to that party is to be taken to be the date on which the amended document is filed, and that is the relevant date for the purpose of computing the limitation period: Fernance v Nominal Defendant (1989) 17 NSWLR 710.

Because an amendment is deemed to date from the date of the original document, there was a “settled rule of practice” that an amendment would not be permitted when it prejudiced the rights of the opposite party as existing at the date of such amendment: Weldon v Neal (1887) 19 QBD 394 at 395. In particular, that an amendment would not be allowed to an originating process which set up a cause of action which was statute-barred at the time of the amendment.

This “settled rule of practice” was abrogated by the former SCR Pt 20 r 40 and DCR Pt 17 r 4 which were in similar, though not identical, terms. Those rules have now been replaced by s 65 of the CPA which is as follows:

Apart from the fact that the relevant provisions are now contained in the Act rather than in the rules, the effect appears to be the same.

The former provisions were discussed and applied in a number of cases including McGee v Yeomans [1977] 1 NSWLR 273; Proctor v Jetway Aviation Pty Ltd [1984] 1 NSWLR 166; and Seas Sapfor Ltd v Far Eastern Shipping Co (1995) 39 NSWLR 435.

The present provisions were discussed and applied in Greenwood v Papademetri [2007] NSWCA 221. In that case it was held that s 65(2)(b) permits multiple parties to replace a single party, and that a plaintiff may make a mistake in the name of a party, not only because the plaintiff mistakenly believes that a certain person, whom the plaintiff can otherwise identify, bears a certain name, but also because the plaintiff mistakenly believes that a person who assumes a particular description bears a certain name. See Mitry v Business Australia Capital Finance Pty Ltd (in liq) [2010] NSWCA 360 for a case where a liquidator sued in his own name to recover a debt due to the company, thereby failing to bring the action in the name of the company. This was truly “a mistake in the name of a party” in the sense contemplated by s  65(2)(b): at [43].

Greater Lithgow City Council v Wolfenden [2007] NSWCA 180 makes it clear that the specific provisions of s 65 do not limit the general power conferred by s 64. Under s 64 an amendment may be allowed even if its effect is to add a statute-barred cause of action which does not satisfy the provisions of s 65. See also East West Airlines Ltd v Turner (2010) 78 NSWLR 1.

A particular limitation in Federal legislation, such as s 34 of the Civil Aviation (Carriers’ Liability) Act 1959, which requires proceedings under that Act to be commenced within two years, will prevail over State legislation, such as the CPA s 65 (Air Link Pty Ltd v Paterson (2005) 79 ALJR 1407), so as to prevent an amendment to plead a new cause of action which is statute-barred at the time of the amendment. In that case, however, it was held that the proceedings had been validly commenced under the Civil Aviation (Carriers’ Liability) Act within the time fixed by that Act, although no reference had been made to the Act.

When leave to amend is granted, it is usually on terms that the party seeking leave pay the costs of the other parties caused by the amendment. This includes costs thrown away by the amendment and costs of any consequential amendments by the other parties.

See section “Setting aside and variation of judgments and orders” at [2-6600].