Driving stoned on marijuana; courtesy National Institute on Drug Abuse

Driving stoned on marijuana; image courtesy National Institute on Drug Abuse

In light of the fact that four states (including Colorado) and D.C. have legalized the recreational use of marijuana, Wallet Hub asked various experts if marijuana can impair driving, and how law enforcement can test for it. One of the experts was William D. Marelich, professor of Psychology at California State University, Fullerton. He said:

‘It can — with slower reflexes one of the impairments. Blood tests won’t work for testing as evidence of marijuana lingers for a week. However, new tests are being developed that are saliva based, such that very recent marijuana use can be detected. No doubt in the future, this type of test will join the alcohol-testing options. How the “legal” use of marijuana will mix with the impairment issue when it comes to driving still needs to be sorted.’

Another expert, Jiang Yu, Director of the Center for Addictions Research at University at Albany School of Social Welfare, told Wallet Hub that although there is no evidence that marijuana causes death, it does impair people’s cognitive and motor abilities. And Ziming Xuan, Assistant Professor of Community Health Sciences at Boston University, School of Public Health, told Wallet Hub that marijuana is frequently found in the blood of drivers involved in fatal and nonfatal car accidents. There is a “direct relationship between blood THC concentration and impaired driving skills,” Xuan said.

To create the rankings, which were authored by Alina Comoreanu, a research analyst at Evolution Finance, Wallet Hub used 15 metrics. They include: criminal penalties (minimal jail time for first and second offenses); when a DUI is automatically considered a felony; how long a previous DUI factors into penalties for a new one; whether or not there are additional penalties for a high BAC; minimum fines for first and second offenses; and whether or not there is protection against child endangerment. In addition, the metrics include: when an ignition interlock is mandatory; if there is an “administrative” license suspension after arrest and before conviction; how long an ignition interlock is mandatory; if alcohol abuse assessment and/or treatment is mandatory; if the state impounds the vehicle after an arrest; the average insurance rate increase after a DUI; whether or not there is a “no-refusal” initiative for rapid search warrants for sobriety testing; whether or not the state provides sobriety checkpoints; and whether or not the state has any other penalties.

Jill Gonzalez, who helped do research for the report, said it is about the severity of laws and not necessarily about how effective they are, as Andrew Koenig reports for The Blade. “Utah, ranked by WalletHub as the seventh strictest state, has by far the lowest percentage of drunken-driving-caused traffic fatalities of 17 percent,” according to a 2013 report on drunken driving fatalities by Mothers Against Drunk Driving, Koenig writes.

Wallet Hub ranked Colorado 28th among the states and D.C. in road safety, as this blog wrote earlier this month. And in 2014, Wallet Hub ranked Colorado at 47 in the category of teen drivers with “under the influence” traffic violations, as this blog reported.

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