Despite a limited medical marijuana program in New York, neither that state nor any other state in the country has an established way to measure driver impairment resulting from marijuana use that has a solid scientific basis. While there are ways to test for THC levels, experts believe that this does not work as an indicator in the same way measuring blood alcohol content does. THC affects people in different ways, and people may have different levels of impairment at higher or lower levels of THC.
This has not stopped companies from racing to try to invent tests that can detect impairment from marijuana instantly in the same way that a Breathalyzer does. One company says its device, which measures THC levels based on a person's breath, is ready for testing and will be available for around $500 to $1,000.
The Automobile Association of America says that motor vehicle fatalities in which marijuana may have been a factor increased in Washington state when the drug was legalized there. However, the organization also says that no adequate testing measures are available. Instead, it recommends that law enforcement establish when a person used marijuana and then look at psychological and behavioral factors to determine impairment.
People who are taken into custody on charges related to driving under the influence of drugs or drunk driving may have a number of questions about what happens next. They might want to speak to an attorney. An attorney may ascertain whether a person's rights were violated and how it was established that the person was impaired. It might be possible to cast doubt on the accuracy of the tests or on law enforcement's account of how the person was detained. A plea bargain might allow a person to plead guilty to lesser charges and could also result in fewer penalties.