# Heydon's Rule / Mischief Rule / Beneficial Construction / Purposive Construction
This rule originated in Heydon's Case (1584) and is often called the Mischief Rule because it focuses on the 'mischief' the statute was intended to remedy.
## When Is the Mischief Rule Applied?
1. Ambiguous words — when the words of the statute are capable of more than one meaning.
2. Literal interpretation defeats the object of the Act — if literal meaning would frustrate the legislature's purpose, the court may depart from the dictionary meaning to advance the remedy and suppress the mischief.
3. Extended meaning is required — for statutes concerning public safety, an extended meaning may be given to give effect to the protective object.
## Essence of the Rule — Methodology
### Step 1: Consider the Historical Background
The court must consider four matters (the famous Heydon's four questions):
1. What was the law before the making of the Act?
2. What was the mischief or defect, which the existing law did not provide for?
3. What is the remedy that the Act has provided?
4. What is the reason for the remedy?
### Step 2: Suppress the Mischief, Advance the Remedy
The court must adopt that construction which suppresses the mischief and advances the remedy the legislature intended.
## Names of This Rule
- Heydon's Rule (from the originating case)
- Mischief Rule (because it targets the mischief)
- Rule of Beneficial Construction (advances the beneficial purpose)
- Purposive Construction (looks at the legislature's purpose)
## Visual: The Four Heydon Questions
```
BEFORE AFTER
+------------------+ +------------------+
| 1. Earlier law? | | 3. New remedy? |
| 2. Mischief? | | 4. Reason for it?|
+------------------+ +------------------+
v
Construe to SUPPRESS mischief
and ADVANCE remedy.
```