The CDC (Center of Disease Control) released their ARDI report (Alcohol Related Disease Impact) stating "teen alcohol use kills about 4,700 people per year, more than all illegal drugs combined " (MADD, 2013, par. 22). .
As a result of no accidents being reported due to marijuana impairment alone, there have been several studies done to determine the effects cannabis has on a person's driving capabilities and mentalities. Two studies performed on the effects of THC and alcohol on driving performance, have almost mirrored findings. According to a study conducted by Robbe in 1998 "their findings support the belief that drivers become over confident after drinking alcohol, but may become more cautious and self critical after consuming small amounts of marijuana " (Ronen, Chassidim, Gershon, Parmet, Rabinovich, Bar-Hamburger, & Shinar, 2010, p.10). This mirrors Ward & Dye's findings in 1999, when they found that people who smoke cannabis demonstrated knowledge of behavioral consequences by applying decreased speeds, increased distance following a car, better lane control, as well as sign detection, sudden lane change task, and the detection of hazards, but when alcohol was involved none of these where detected (Ronen, Gershon, Drobiner, Ravinovich, Bar-Hamburger, Mechoulam, & Shinar, 2008). .
These studies and reports support the claims that marijuana use while driving is not as deadly or dangerous as driving under the influence of alcohol. There are well known documented facts proving smoking tobacco can lead to lung disease, cancer, and eventually death. It is a typical belief that smoking marijuana can lead to all the health issues including death that tobacco does. Therefore, a twenty year study conducted on the effects of marijuana use on the lungs was conducted, and it echoed the results done in smaller studies conducted by Dr. Tashkin, an UCLA professor, and Dr. Ware, a professor at McGill University.