NORML’s recent study at Hartford hospital in Connecticut and the University of Iowa’s Carver College of Medicine states the following: Drivers exhibit no indications of unimpaired driving.
YEA, RIGHT! NOT LIKELY! WHAT A CROCK! Obviously another study run by those who want pot legalized! 
Drivers who use pot, and take a driving test are totally focused, 100% on showing how they can drive w/o any mistakes, w/o any indication of being impaired.
This is obviously the reason they seem to do better than expected.
Yet, on the road, without being graded and scored, the truth becomes more than apparent; their focus there, …. is on music and munchies! Obviously, even the statement below proves it!
“Investigators reported. “Smoking THC cigarettes caused drivers to drive slower in a dose-dependent manner, while alcohol caused drivers to drive significantly faster than in ‘control’ conditions.” ” 
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