What is the main issue in Scott v. Shephard?

Whether the defendant’s unlawful act remained the legal cause of the injury or a new intervening force broke the chain of causation.

What rule did the court apply?

A person who commits an unlawful act is treated as the doer of all natural and probable consequences that follow from that act.

Why weren’t the bystanders liable?

They were not free agents; they moved the squib only to protect themselves or their goods, so their acts did not break the chain.

What is the takeaway on causation?

Necessary self-protective reactions usually do not count as a novus actus; the original wrongdoer remains liable.

Is this a trespass or negligence case?

It is framed as trespass: the injury was treated as directly caused by the defendant’s unlawful act of throwing the squib.

scott-v-shephard-1773-novus-actus-interveniens

Scott v. Shephard (1773) — The Squib Case

Unlawful act, flying squib, and the chain of causation: when do others’ reactions break it? A clean, classroom-style explainer.

Torts King’s Bench 1773 96 Eng. Rep. 525 ~7 min read

Author

: Gulzar Hashmi

Location

: India

Primary Keywords

: Scott v Shephard, novus actus interveniens, trespass, causation

Secondary Keywords

: squib case, unlawful act, directness, free agents, chain of causation

Publish Date

: 31 Oct 2025

Slug

: scott-v-shephard-1773-novus-actus-interveniens

Quick Summary

Scott v. Shephard (the “squib case”) holds that the original wrongdoer stays liable when others only react for safety. Their necessary reactions do not break the causation chain. The defendant’s unlawful throw was treated as the direct cause of the injury.

Issues

Did a novus actus interveniens break the chain, or did the defendant’s unlawful act remain the legal cause?

Rules

Anyone who does an unlawful act is treated as the doer of all its natural and probable consequences. Safety-driven reactions by others usually do not break the chain.

Facts (Timeline)

Timeline of the squib’s path across the market in Scott v. Shephard

Unlawful Throw: Defendant threw a lit squib (small firework) into a crowded market.

First Reactions: Yates and Willis tossed it away to protect themselves.

Further Reaction: Ryal threw it again to save his goods.

Injury: The squib struck the plaintiff’s face; he lost the use of one eye.

Suit: Plaintiff sued the original thrower in trespass.

Arguments

Appellant / Plaintiff

The defendant’s unlawful throw started the danger.
Others moved it only for safety; causation remains with the defendant.

Respondent / Defendant

Independent acts by others broke the chain.
Any injury was due to new intervening acts, not the original throw.

Judgment (Held)

Judgment summary icon for Scott v. Shephard

The court found for the plaintiff. The defendant’s unlawful act remained the legal and direct cause. The bystanders acted from necessity, so their acts did not break the chain.

Outcome: Liability attached to the original thrower.
Reason: Reactions were compelled by safety, not free choices.

Ratio Decidendi

Where a defendant commits an unlawful act and others react only to avoid harm, their reactions are treated as a continuation of the defendant’s act. Causation remains with the defendant.

Why It Matters

Key case on novus actus interveniens and directness in trespass.
Clarifies that compelled, safety-based reactions usually do not sever causation.
Essential for exam problems on chains of events and crowd reactions.

Key Takeaways

Unlawful act = liability for its natural/probable results.
Safety reactions rarely count as a novus actus.
Directness can make it trespass, not just negligence.

Mnemonic + 3-Step Hook

Mnemonic: “Squib Starts, Chain Stays”

Step 1: Spot the unlawful start.
Step 2: Ask if others acted for safety only.
Step 3: If yes, no break—defendant remains liable.

IRAC Outline

Issue: Did bystanders’ acts break causation or is the defendant’s unlawful throw the legal cause?

Rule: Unlawful actor is liable for natural and probable consequences; compelled safety reactions do not break the chain.

Application: Yates, Willis, and Ryal acted only to protect themselves/property. Their moves were necessary, not voluntary free choices.

Conclusion: Chain was unbroken; defendant is liable.

Glossary

Novus Actus Interveniens: A new, independent act that breaks the chain of causation between the defendant’s conduct and the harm.
Free Agent: A person acting voluntarily and independently, not merely reacting for safety.
Trespass: Direct interference causing injury; here, the injury was treated as directly caused by the defendant’s unlawful act.