

Why your phone records are not, in fact, protected by the 4th amendment - anigbrowl
http://caselaw.lp.findlaw.com/scripts/getcase.pl?navby=CASE&court=US&vol=442&page=735

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anigbrowl
Only legal nerd enjoy reading Supreme Court decisions, but here's a quick
breakdown of how to read this (you don't have to read the whole thing to get
it).

The first paragraph, reproduced below, is the 'summary,' which tells you what
the case is about:

 _The telephone company, at police request, installed at its central offices a
pen register to record the numbers dialed from the telephone at petitioner's
home. Prior to his robbery trial, petitioner moved to suppress "all fruits
derived from" the pen register. The Maryland trial court denied this motion,
holding that the warrantless installation of the pen register did not violate
the Fourth Amendment. Petitioner was convicted, and the Maryland Court of
Appeals affirmed._

Next, the part after the word HELD: is known as _the holding_ , and this is
the part of the ruling which has legal force and constitutes _precedent_
designed to guide courts going forward into the future.

Finally, the _opinion_ (beginning with 'Mr. Justice Blackmun delivered the
opinion of the court:') is an explanation of what the holding means by one of
the judges who was in the majority (which particular judge is assigned at the
whim of the Chief Justice, if s/he is with the majority, or otherwise the most
senior Justice in the majority group). A _concurrence_ is a supplementary or
orthogonal explanation from another justice who supports the decision but for
a slightly different legal reason. A _dissent_ is an explanation of how a
justice on the losing side thinks the law should have been interpreted, or
addressing some perceived flaw in the opinion.

The opinion, concurrences, and dissent are (of course) of great interest to
lawyers and judges who have to consider similar cases in the future, but it's
important to remember that they're _not law_ (lawyers collectively refer to
them as _dicta_ , meaning 'speeches' or 'sayings'.). Only the holding is law.
I have seen decisions where the holding set precedent and the opinion is so
logically or factually flawed as not to make sense, but bear in mind that you
can't overturn a court's decision solely by pointing out flaws in the opinion,
because the opinion itself is not law. You have to either point a
contradiction or falsity within the holding itself (rare) or start over with
reference to external sources (Constitution, legislation, prior precedent) to
show why the holding is wrong.

It's very important, and often difficult, to distinguish between the holding
and the _dicta_. I mention this because many people, and especially hackers,
are liable to get caught caught in some ambiguity or linguistic argument about
the contents of an opinion and mistakenly think that they've thereby
invalidated the holding. Lawyers and even courts are not immune to this kind
of mistake, and cases sometimes come apart because one side has relied too
heavily on a particular sentence in an opinion.

