• A cause of action for negligence is
frequently described as having four
– Duty
– Breach
– Causation
– damage
• Palsgraf案
• A duty runs only to those who are within
the foreseeable ambit of danger.
• If there is “a risk reasonably to be
perceived” to the plaintiff, there is a duty to
be obeyed.
The negligence Balancing Test
• Nussbaum v. Lacopo案
• There is a remote possibility of personal
injury or property damage is ordinarily not
• Person cannot to be expected to guard
against harm from events which are so
unlikely to occur that the risk, although
cognizable, would commonly be
• United States v. Carroll Towing Co.案
• Learned Hand法官
• Liability exists if the burden the defendant
would have to bear to avoid the risk (B) is
outweighed by the gravity of the loss (L)
times the probability (P) of the threatened
harm (B<LP)
• The negligence inquiry also takes into
account the utility of the defendant’s
conduct and the availability of alternatives.
• A balancing test may be employed to determine
whether the defendant’s conduct has created an
unreasonable risk of harm.
• In general, the utility of the defendant’s action
and the burden and feasibility of taking
preventive measures are weighed against the
gravity of the threatened harm and the
probability that such harm will ensure
• The utility of a given course of conduct is a
function of:
– The social value of the interest the defendant
seeks to advance
– The likelihood that the conduct will advance
the desired objective
– The availability of alternative
• Whether there is a viable alternative is a
question of both technical feasibility and
whether the alternative could entail high
economic and non-economic costs
• The gravity of the threatened harm is a
function of:
– The social value of the interest imperiled
– The extent of the harm that is threatened
– The number of persons who are likely to be
• The reasonable, prudent person is an
entirely hypothetical character; thus, it is
an error to tell jurors that the question for
determination is whether they, as
reasonable persons, would have done
differently than the defendant.
• In Williams v. Bright, the issue was
whether the plaintiff had unreasonably
failed to mitigate(緩和) damages due to
her religious beliefs as a Johovah’s
Witness, which allegedly precluded her
from having a knee operation because the
procedure would require a blood
• Most jurisdictions hold that the fact that an
actor is mentally deficient(缺陷), or
temporarily or permanently insane(精神
錯亂), is normally not a relevant
consideration in determining whether the
actor behaved reasonably.
(professional malpractice)(頁96)
• For example, a client(客戶) should not
have to inquire whether a lawyer the client
may hire believes that client information
should be held confidential(保密), that
conflicts of interest (利益衝突)should be
avoided, or that it is necessary to do legal
research before giving advice on an
unsettled question of law.
法律不當執業(legal malpractice)
• If an attorney has failed to take
appropriate action within the statute of
limitations(時效), the plaintiff ordinarily
must establish not only that the deadline
was missed, but that had the statute not
run, the plaintiff would have prevailed in
the underlying action.
法律不當執業(legal malpractice)
• Transactional errors may entail a
somewhat different approach to proof of
causation(因果關係) of damage. For
example, where a lawyer is negligent in
arranging the sale of business, some
courts allow the aggrieved(受侵害的)
client to recover only if the client can show
that but for the error there would have
been a more advantageous result.