D negligence must be both actual and proximate cause to be liable
1.Cause in Fact
a.“But for” D’s negligence, P’s injuries would not have occurred.
Immediate connection between act and injury
b.“Substantial Factor”
i.Two forces acting: if two parties act causing one harm to P.  Both are liable if each party’s conduct was a substantial factor in causing the injury. (Ex. R.R. Fire Case)
c.Alternative Liability (Summers v. Tice)
i.Small number of tortfeasors
ii.All being sued
iii.Know that at least one of them is responsible
iv.  Equal chance that all tortfeasors are potentially liable
v.   Burden of proving no liability is on each Defendant
d.    Loss of Chance (Herskovits v. Group Health Cooperative – Reduced chance of dying has value)
i.   Herskovits Rule – damages based solely on damages caused directly by premature death such as lost earnings and additional medical expenses
ii.  All or Nothing –
A.    But for D’s negligence, P had a 51% chance of survival, then D liable for all damages.
B.    But for D’s negligence, P had a 49% chance of survival, then P recovers nothing.
iii.  King’s Approach: If you have a condition that decreases your life expectancy, then you shouldn’t be treated as if you have a full life expectancy.
Ex.: 20% of a 10-year life expectancy vs. 20% of a full life expectancy
iv.   Thin Skull Rule: (In opposition to King’s Formula) With the Thin Skull rule, you take P as you find him, i.e., regardless of pre-existing condition, you treat apportionment of damages based on a full life expectancy standard
v.    Judicial Response to Loss of Chance – Split of Authority
e.    Increased Risk
i.  Toxic Torts – Mass Exposure Cases – Ex. Agent Orange
a.    Future Torts – The probability of contracting the disease is so low that you will not be compensated.  However, you may be compensated for the increased medical monitoring that you will need.
f.    Market Share Liability (DES case – Skipwoth v. Lead)
i.   Following Factors Required
a.    All named defendants are potential tortfeasors
b.    The allegedly harmful products are identical and share the same defective qualities (fungible)
c.    The P is unable to identify which D caused her injury through no fault of her own
d.    All of the manufacturers, which created the defective products during the relevant time, are named as Ds.
ii.  You cannot be charged for more liability than the amount or % of market that you bear.
iii. The burden of proof shifts to any 1 individual D to prove they were not in the market at the time of the injury.

2.    Proximate Cause (Legal Causation, Direct Cause)—relationship b/w conduct of D and harm suffered by P must be close enough to justify causation

a.    Duty (Palsgraff – P injured on platform by explosion resulting from guard dislodging package of explosives out of the hands of a passenger)
i.   Question of Law
ii.   Cardozo –
i.   Is this particular P owed a duty?  Is this P foreseeable or in the zone of danger?
ii.   Cardozo Rule: Zone of Danger and “Eye of Ordinary Vigilance” – ? No duty owed to P; duty only to passenger
iii.  Andrews Dissent – D liable for all harm regardless of whether or not the injury to that degree was foreseeable
i.    Once there’s a duty, there’s a duty to the WHOLE WORLD
ii.    Superceding/Intervening Cause – to determine S/I cause, look for human agents?
Time and space important but not conclusive
— key in ignition liability ends if accident happens several days after theft

Note: If there is no duty owed, then you don’t even get to direct cause or reasonable foreseeability b/c there is no NEGLIGENCE!!!!!!

iv.  Green Analysis – Look at risk of harm and ask is this risk protected by a duty?  The duty/risk analysis is at the heart of the inquiry. (Refinement of Cardozo)

b.    Direct Cause (Polemis – falling board caused spark)
i.   Where negligence is direct cause of injury, actor is liable for full extent of injuries
regardless of foreseeability
ii.   Wagon Mound ruled that it was unfair to hold actor liable for full extent of injuries
Question of fact for jury

c.    Foreseeability  (Wagon Mound – floating rag caught fire and spread through oil in water)
i.   Question of fact – jury
ii.   D only liable for damages that are reasonably foreseeable.