CHAPTER 11 Substance and Procedure

• Date: 07 April 2025

276

CH AP TER 11

SUBSTANCE AND

PROCEDURE

A. INTRODUCTION

The previous chapter introduced the process of characterizing particular

legal rules as either substantive or procedural. This characterization is

chief‌ly important because the forum nearly always applies its own pro-

cedural law, even in cases where a choice of law rule leads to foreign law

being applied to resolve the dispute.1 For example, a claim in contract

may be governed by New York law but the Ontario court will still use

Ontario rules of evidence in the dispute. It does not sit as though it was

a New York court and does not apply any procedural law of New York.

The court will therefore have to determine which rules from each legal

system are substantive and which are procedural.

Exceptionally, a court might apply a procedural rule of another

country. A possible example is in assessing the validity of the service of

documents on a party outside the forum. Rather than insisting that such

a service be made in accordance with the forum’s procedural rules, the

forum might accept the service as valid if it was made in accordance with

the law of the place where the party was served.2

1 Iraqi Citizens v Ministry of Defence (No 2), [2016] UKSC 25 at para 1.

2 See, for example, r 17.05(2) of Rules of Civil Procedure, RRO 1990, Reg 194

[Ontario Rules]. On this and other exceptions to the general rule, see Richard

Garnett, Substance and Procedure in Private International Law (Oxford: Oxford

University Press, 2012) at 3 and 37.