Also known as: post hoc · post-hoc ergo propter hoc · post hoc fallacy
Written by attorneys · grounded in primary & secondary sources — see below
A logical fallacy that infers a causal connection between two events merely because one followed the other in time.
Parker Phillips sued a university in federal court. The judge had once served as a trustee negotiating with the university but learned of the link only after judgment. Parker argued that the timing alone proved the judge must have known earlier and should have recused. The court held that the objective recusal standard under §455(a) can warrant vacatur even without actual knowledge when the violation undermines public confidence.
Police questioned Pedro Pacheco without counsel and learned the location of a victim's body. The defense claimed the body must be suppressed because the questioning preceded the discovery. The court held that the evidence would have been found anyway through an independent search already underway, so timing alone did not prove causation.
Select any source to read its text and confirm it supports the definition.
Priscilla Parks obtained a large punitive award against her insurer after a delayed claim payment. She argued that the verdict must have stemmed from the insurer's earlier bad-faith letters because they preceded the trial. The reviewing court found the argument rested on sequence rather than proof that the letters actually drove the jury's decision.
Pilar Pena bought shares in Basic Inc. and later sold at a loss. She asserted that the company's earlier public statements must have caused the price drop simply because the statements came first. The court required evidence of actual reliance and market impact rather than mere chronological order.
Officers stopped Patricia Patel's car and found contraband in a closed container. She claimed the container search must have been unlawful because it followed the traffic stop. The court upheld the search under the automobile exception and rejected any inference of illegality drawn solely from the order of events.
Deputies allowed a reporter to accompany them when serving a warrant at Portia Price's home. Price argued that the presence of the media must have violated the Fourth Amendment because the ride-along occurred during the search. The court examined whether the media presence itself was unreasonable rather than assuming illegality from timing alone.
Courts reject verdicts that rest only on the fact that negligence and injury occurred in sequence. The plaintiff must show that the negligence actually produced the harm rather than merely preceding it.
No. A plaintiff must establish that the warranty breach caused the loss rather than simply showing that the injury followed use of the product.
An expert may not testify that one event caused another solely because the second event followed the first. The opinion must rest on a reliable scientific or medical basis beyond temporal sequence.
The objective recusal standard focuses on what the judge reasonably should have known at the time of the proceedings. Later discovery of a disqualifying interest does not automatically prove earlier actual knowledge.
…District Court permitted the plaintiff to proceed on her fraud-on-the-market theory. Thus, Abrams demonstrates how easily a post hoc statement will enable a plaintiff to bring a fraud-on-the-market action — even in the rare case where a plaintiff is frank or foolhardy enough to admit initially that a factor other than…