> ## Documentation Index
> Fetch the complete documentation index at: https://lawmaxxing.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Breach of Duty & Causation

> Session 9

## I. Breach of Duty: Res Ipsa Loquitur (Review)

### 1. Black Letter Law / Rule

**Res Ipsa Loquitur** ("The thing speaks for itself") is one of the three methods to prove **Breach of Duty** (alongside "conduct falling below the standard of care" and "negligence per se").

* **Elements:** To utilize *Res Ipsa Loquitur*, the Plaintiff must prove:
  1. The accident causing the injury is of a type that does not ordinarily happen in the absence of negligent conduct.
  2. The instrumentality causing the harm was in the **sole and exclusive control** of the defendant.
* **Legal Effect:** Successfully invoking *Res Ipsa Loquitur* creates an **evidentiary presumption of breach**. This shifts the burden of proof to the Defendant to rebut the presumption.

### 2. Key Cases

* **Larson v. St. Francis Hotel**
  * **Facts:** A heavy armchair was thrown out of a hotel window, injuring the plaintiff on the street below.
  * **Holding:** *Res Ipsa Loquitur* did not apply. The hotel did not have **exclusive control** over the furniture in the rooms because guests (occupants) had control. To prevent this would require a guard in every room.
* **Akiona v. United States**
  * **Facts:** A grenade from the Vietnam era exploded and injured plaintiffs 20 years after the government possessed it.
  * **Holding:** *Res Ipsa Loquitur* failed. The government did not have exclusive control over the instrumentality because 20 years had passed, and it could have been transferred to third parties.
* **James v. Wormley**
  * **Facts:** A guide wire was left in a patient's chest after a biopsy. Plaintiff did not provide expert testimony.
  * **Holding:** While leaving a foreign object (like a sponge) is often common knowledge negligence, specific medical decisions involving guide wires require expert testimony to establish the standard of care. Without it, the plaintiff could not eliminate other causes or prove exclusive control.

***

## II. Causation: Overview

### 1. Black Letter Law / Rule

Tort law is a fault-based system; injury alone does not equal recovery. The Plaintiff must prove a causal link between the Breach and the Damages. Causation is divided into two distinct requirements:

1. **Causation in Fact** (Actual Cause).
2. **Proximate Cause** (Legal Cause).

**Note:** One must establish **Causation in Fact** *before* analyzing **Proximate Cause**. There is a "firewall" between them.

***

## III. Causation in Fact (Actual Cause)

### A. The "But-For" Test (Single Defendant)

#### 1. Black Letter Law / Rule

* **Concept:** *Sine Qua Non* ("Without which it cannot be").
* **The Test:** "But for the defendant's negligent conduct (act), the plaintiff would not have been injured".
  * If the injury would have occurred regardless of the defendant's negligence, the defendant is *not* the cause in fact.
  * With a single defendant, this is the only test needed.

#### 2. Key Cases

* **Perkins v. Texas and New Orleans Railroad Co.**
  * **Facts:** A train was speeding (Negligence Per Se). A car drove onto the tracks, and the passengers were killed. Evidence showed the train could not have stopped in time even if it had been traveling at the legal speed limit.
  * **Holding:** The speeding was **not** the cause in fact. **But for** the speeding, the accident still would have happened. Therefore, the breach did not cause the injury.
* **Kramer Service, Inc. v. Wilkins**
  * **Facts:** Plaintiff was cut by falling glass in a hotel (negligence). The cut later developed into skin cancer. Experts disputed whether the cut caused the cancer.
  * **Holding:** Causation failed regarding the cancer. It is not enough that the negligence *possibly* caused the harm; the plaintiff must prove it was **more likely than not** (greater than 50% probability) the cause.

***

### B. Concurrent Causes (Multiple Defendants)

#### 1. Black Letter Law / Rule

* **Definition:** Where several acts combine to cause the injury, but **none of the acts standing alone would have been sufficient**.
* **The Test:** The **But-For Test** applies and works here.
  * "But for *any* of the acts, the injury would not have occurred".

#### 2. Key Cases

* **Hill v. Edmonds**
  * **Facts:** A truck driver negligently parked without lights in the middle of the road. A car driver negligently failed to see the truck and hit it. Neither act alone would have caused the accident.
  * **Holding:** Both defendants are causes in fact. But for the truck parked there, no accident. But for the car driver's failure to look, no accident.

***

### C. Joint Causes (Multiple Defendants)

#### 1. Black Letter Law / Rule

* **Definition:** Where several causes **concur** (come together) to bring about an injury, and **any one alone would have been sufficient** to cause the injury.
* **The Issue:** The But-For Test **fails** here (because the injury would have happened anyway via the other cause).
* **The Test: Substantial Factor Test.**
  * If the defendant's conduct was a **substantial factor** in causing the injury, they are liable.

#### 2. Key Cases

* **Anderson v. Minneapolis, St. P. & S. S. M. Ry. Co.**
  * **Facts:** Two separate fires (one set by Defendant 1, one by Defendant 2) merged and burned down the plaintiff's barn. Each fire alone was sufficient to destroy the barn.
  * **Holding:** Both defendants are liable. Since the But-For test fails, the court asks if each fire was a **substantial factor**. Since both were substantial factors, both are causes in fact.

***

### D. Alternative Causes (Multiple Defendants)

#### 1. Black Letter Law / Rule

* **Definition:** Where two or more persons have been negligent, but there is **uncertainty** as to which *one* caused the plaintiff's injury.
* **The Issue:** The plaintiff cannot prove causation against either specific defendant using the But-For or Substantial Factor tests.
* **The Rule:** The **burden of proof shifts to the defendants**. Each defendant must show that their negligence was **not** the actual cause to exculpate themselves. If they cannot, they are liable.

#### 2. Key Cases

* **Summers v. Tice**
  * **Facts:** Two hunters negligently shot shotguns in the direction of the plaintiff. One pellet hit the plaintiff's eye, blinding him. It was impossible to know which gun fired the specific pellet.
  * **Holding:** The burden shifts to the hunters. Since neither could prove the pellet didn't come from their gun, both were liable.
* **Sindell v. Abbott Laboratories (Market Share Liability)**
  * **Facts:** Plaintiff developed cancer due to her mother taking DES (a drug) while pregnant. The drug was a generic manufactured by hundreds of companies; Plaintiff could not identify which specific manufacturer made the pills her mother took.
  * **Holding:** Burden shifts to defendants. If they cannot prove they did not manufacture the specific pills, they are liable proportional to their **market share** of the drug at the time.

#### 3. Nuance: Lost Chance of Recovery

* **Smith v. Providence Health & Services:** Where medical negligence delays diagnosis (e.g., stroke), reducing a patient's chance of recovery (even if the chance was \< 50%), plaintiff may recover for the **loss of a chance**.

***

## IV. Expert Testimony (Daubert Test)

### 1. Black Letter Law / Rule

When introducing novel scientific evidence (often required to prove causation), the trial court judge acts as a gatekeeper for admissibility.

### 2. The Daubert Factors

To determine relevance and reliability, courts look at:

1. Whether the theory/technique creates scientific knowledge that can be/has been **tested**.
2. Whether it has been subject to **peer review and publication**.
3. Whether it is **generally accepted** within the relevant scientific community.

***

## V. Proximate Cause (Legal Cause)

### 1. Black Letter Law / Rule

* **Definition:** Proximate cause is a **legal doctrine** (and liability-limiting tool) that **cuts off liability** for harm, even though the harm was, in fact, caused by the defendant's negligent conduct.
* **Rationale:** It would be **unfair or unjust** to hold the defendant liable for infinite consequences of their act.
* **General Scope:** A defendant is liable for all harmful results that are the **normal incidents of** and within the **increased risk** caused by their acts.

### 2. Direct Causes

* **Definition:** A case where the facts present an **uninterrupted chain of events** from the defendant's negligent act to the plaintiff's injury (no intervening acts).
* **Foreseeability Rule:** If a particular harmful result was **at all foreseeable** from the negligent conduct:
  1. The **unusual manner** in which the injury occurred is **irrelevant**.
  2. The **extent of the damage** is **immaterial** (Eggshell Skull Doctrine).
* **Unforeseeable Type:** If an **entirely different** or **unforeseeable type** of harmful result occurs, the defendant is **not liable**.

### 3. Nuance: The Eggshell Skull Doctrine

* "You take your plaintiff as you find them".
* Even if the plaintiff is uniquely fragile (e.g., has an eggshell skull), the defendant is liable for the full extent of the injury, even if a normal person would have suffered less harm.