[tz] Danish Time not UTC

Random832 random832 at fastmail.com
Thu Nov 10 16:49:42 UTC 2016

On Thu, Nov 10, 2016, at 11:18, Clive D.W. Feather wrote:
> Random832 said:
> >> The Directive in question views UT, UTC, GMT, and various other terms as
> >> being equivalent, so doesn't tell us anything.
> > Well, are they not?
> UT and UTC definitely aren't the same.

To a layperson, "UTC" appears to be "UT" with an adjective attached. In
technical terms, as far as I can tell, "UT" doesn't seem to exist, and
it's not clear that UT1 has a better claim to it than UTC. But
regardless, I meant this to set up my question on legal definitions as
may be distinct from technical definitions.

> > What's the *legal* definition of UT and GMT?
> To the best of my knowledge neither term is defined in either UK or EU
> law.
> Which means that - if it was relevant - a court would either look at the
> understanding of the person on the Clapham omnibus (possibly with a
> diversion via the OED) or would ask to be briefed by an accepted expert.

One has to wonder whether they would take into account whether there was
really legislative intent to require continuous adjustment by fractional
seconds. But it's hard for me to imagine what sort of case the
difference might be relevant to in the first place.

Incidentally, on the subject of time zone laws not specifying UTC, the
US timezones were originally defined in 1918 as the mean time of some
respective longitude each west of Greenwich, and wasn't amended to
specify hours from UTC until 2007 [Pub. L. 110–69, title III, §
3013(c)(3), Aug. 9, 2007, 121 Stat. 598; this and the text of previous
versions mentioning longitude (including an amendment as recent as 2000
defining Chamorro Standard Time as 150 degrees east) can be found at

The 2007 amendment also, amusingly, moved the southern part of Idaho to
Mountain Time from Central Time.

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