> No belt and 90 mph, I'd like to get a ticket for either in Jersey and
> have my say in court. Tricky as to what agencies have access to the
> SIRS module info after a deployment.

Hopefully as a mere matter of getting a ticket -- actually stuff the
car at 90 with no belt, "you should have such problems."

To get back to the original poster's question: I doubt that they
would find a speedo stuck at 90 (in the car, that is; if your
Speedo gets stuck at 90; well, you and all your buddies at the
senior center should have such problems). Needles getting frozen at
some reading is an ancient theme from fictional and apparently some
factual accounts of aircraft crashes, violent disruptions of one's
person in the era of mechanical wrist watches, etc. I am thinking
that that takes extreme g's, especially in the case of an instrument
where the position of the needle is a dynamic rather than a static
affair (stopping a mechanical clock might be a lot easier to arrange,
John Cameron Swayze notwithstanding).

A quick glance through the literature of a field not my own indicates
that a slap mark on the *face* of a speedometer is what investigators
are usually looking for after a motor vehicle crash, not the needle's
actually being frozen. Mythbusters could doubtless have a lot of
fun with some old jalopies and an abandoned runway in this regard.

As others have pointed out, there are several other ways of
determining the crash speed through forensics at the general crime
scene, perhaps onboard computers, and occupants coming clean about the
situation.

Cheers,
--Joe