[A CA Guy]

They do blood tests in an accident where people are hurt bad.
Pot comes up, and if driving home from work they could find themselves in a lawsuit because of deep pockets.

[rb22982]

That is not true, what you say can already occur today and there is no case or precedence for it. The only way that is possible is it was allowed to be smoked at work. That same logic would put gun makers at fault for gun whackos, same with knives, etc.

[HairOfTheDog]

A blood test will not prove DUI with pot. A blood test will show marijuana residual for three weeks, long after intoxication is gone, and there is no way to tell when the intoxication occurred.

There are some eye-reflex and observational kinds of tests police can do that are admissable, but any attorney can counter a simple blood test.

[Ramius]

Pot comes up, and if driving home from work they could find themselves in a lawsuit because of deep pockets.

That's not true of alcohol. Why not?