Drinking vs. Non-drinking Drivers

	Per MADD's figures, non-drinking drivers are 8 times more dangerous than drinking drivers.
	Per police reports, non-drinking drivers are 182 times more dangerous than drinking drivers.
	Outlawing non-drinking drivers would reduce the annual costs for motor vehicle crashes by $130-190 billion.

Americans' annual consumption of pure alcohol is 2.1 gallons or 277 ounces per capita.  The Gallup Poll  notes that a third of the population abstains from drinking completely, and that 60% has had a drink within the last week, 35% of whom had a drink within the last 24 hours.  65 million men and 53.7 million women over age 14 consumed 76 billion ounces of alcohol, which is an average of 1.75 ounces each per day.  Men consume an average of 2.3 ounces each per day and women consume an average of one ounce each per day.   This is enough to keep the blood alcohol content (BAC) of each of these 65 million men above 0.17 and each of these 53.7 million women above 0.09 each and every day of the year.

The Montana Highway Traffic Safety Division notes that "An average person's body will eliminate alcohol at the rate of .015 BAC per hour."  This means that it takes 11 hours for the average man who drank 2.3 ounces of alcohol and 6 hours for the average woman who drank one ounce of alcohol to reduce their BAC to 0.015.

The higher probability that non-drinking drivers will have an accident contributes to an increase in the accident rate for drinking drivers.  To determine exactly how much higher the accident rate for drinking drivers is because of non-drinking drivers it is necessary to calculate the rate at which both drinkers and non-drinkers are expected to have an accident.  The total number of accidents that a drinking driver is expected to have per million miles is the sum of his probability of having a single driver accident, plus the square of this number to represent a two driver accident involving another drinking driver, plus his expected number times the number of accidents per million miles which a non-drinking driver is expected to have, or N_n.  If we let

N_d  = The number of single driver accidents that drinking drivers is expected to have per million miles.

N_d² = The number of accidents per million miles that a drinking driver is expected to have with another drinking driver.

N_d x N_n = The number of accidents per million miles that a drinking driver is expected to have with a non-drinking driver.

then we have two equations and two variables. 

Number of accidents per year by drinking drivers = 1,400,000 accidents

Number of miles driven per year by drinking drivers = 1 trillion miles

N_d ⁺ N_d² + N_d x N_n = 1.4 accidents per million miles

The equation for non-drinking drivers is similar:

N_n  = The number of single driver accidents that non-drinking drivers would be expected to have per million miles.

N_n² = The number of accidents per million miles that a non-drinking driver would be expected to have with another non-drinking driver.

N_d x N_n = The number of accidents per million miles that a drinking driver would be expected to have with a non-drinking driver.

Number of accidents per year by non-drinking drivers  = 2,800,000 accidents

Number of miles driven per year by non-drinking drivers = 1,000,000 million miles

Accident rate per million miles = 5.6 accidents per one million miles = 1 accident per 178,571 miles

N_n ⁺ N_n² + N_d x N_n = 5.6 accidents per million miles

N_d = (5.6 - N_n - N_n²)/N_n

(5.6 - N_n - N_n²)/N_n + (31.36 -11.2N_n - 10.2N_n² + 2N_n³ + N_n⁴ )/N_n² + 5.6 -N_n ^-N_n² = 1.4    

5.6N_n - N_n² - N_n³ +  31.36 -11.2N_n - 10.2N_n² + 2N_n³ + N_n⁴   + 5.6N_n^{2 -} N_n^{3 -} N_n^{4 =} 1.4N_n²

31.36 -5.6N_n - 7N_n² = 0

7N_n²  +5.6N_n = 31.36

N_n = 1.755 = Number of accidents per million miles that a non-drinking driver is expected to have.

N_d = 0.436 = Number of accidents per million miles that a drinking driver is expected to have.

If non-drinking drivers were not colliding with drinking drivers, and if drinking drivers drove all 1,500 billion of the miles currently driven by both non-drinking and drinking drivers, there would be (N_d  + N_d²) x 1,500,000 million miles = 939,144 drivers in accidents per year, which is only 22.4% as many are there currently are.

If only non-drinking drivers drove all 1,500 billion of the miles currently driven by both non-drinking and drinking drivers, there would be (N_n   + N_n²) x 1,500,000 million miles = 7,252,538 drivers in accidents per year, which is 73% more than there currently are.

If only non-drinking drivers drove there would be 7.7 times as many accidents than if only drinking drivers drove.

But there is a serious problem with MADD's statistics, because where MADD claims that one third [and where some headlines proclaim that one half] of all serious or fatal accidents are alcohol-involved, reports from police departments across the nation show that only 4% are.  This means that 96% and not 66% of accidents involve only non-drinking drivers, which changes the accident probabilities significantly.

sausalcoholpolice.pdf

(N_d +  N_d²  + N_dN_n) x 1,000,000 million miles driven = 170,000 accidents

N_d +  N_d²  + N_dN_n = 0.17

The equation for non-drinking drivers is similar:

(N_n +  N_n²  + N_nN_d) x 500,000 million miles driven = 4,030,000 accidents

N_n +  N_n²  + N_nN_d = 8.06

N_d = (8.06 - N_n - N_n²)/N_n

(8.06 - N_n - N_n²)/N_n + (64.96 -16.12N_n - 15.12N_n² + 2N_n³ + N_n⁴ )/N_n² + 8.06 -N_n ^-N_n² = 0.17

8.06N_n - N_n² - N_n³ +  64.96 -16.12N_n - 15.12N_n² + 2N_n³ + N_n⁴   + 8.06N_n^{2 -} N_n^{3 -} N_n^{4 =} 0.17N_n²

64.96 - 8.06N_n - 8.23N_n² = 0

8.23N_n²  +8.06N_n = 64.96

N_n = 2.6321 = Number of accidents per million miles that a non-drinking driver is expected to have.

N_d = 0.05 = Number of accidents per million miles that a drinking driver is expected to have.

If non-drinking drivers were not colliding with drinking drivers, and if drinking drivers drove all 1,500 billion of the miles currently driven by both non-drinking and drinking drivers, there would be (N_d  + N_d²) x 1,500,000 million miles = 78,750 drivers in accidents per year, which is only 1.9% as many are there currently are.

If only non-drinking drivers drove all 1,500 billion of the miles currently driven by both non-drinking and drinking drivers, there would be (N_n   + N_n²) x 1,500,000 million miles = 14,340,076 drivers in accidents per year, which is 3.4 times more than there currently are.

According to police reports only, if only non-drinking drivers drove there would be 182 times as many accidents than if only drinking drivers drove.

	Per Traffic Safety Facts' "Vehicle Miles of Travel, 1975-1996" http://www-fars.nhtsa.dot.gov/www/cfm/library/rpt_info.cfm?index=Trends:Occupants&recordid=0   Americans drove passenger cars 1,500 billion miles in 1995.
	One third of those miles or 500 billion were driven by non-drinking drivers and two thirds or 1,000 billion by drinking drivers.
	MADD claims that one third of all injury or fatal accidents involve a drinking driver, and two thirds do not 1.4 million drinking drivers and 2.8 million non-drinking drivers were involved in fatal and injury crashes in 1996.
	Per Traffic Safety Facts' "Drivers Involvement in Crashes" from the FARS data base http://www-fars.nhtsa.dot.gov/www/cfm/library/rpt_info.cfm?index=People:Drivers&recordid=0 there were a total of 4.2 million drivers in auto accidents in 1996.
	1.4 million drivers were in single driver accidents and 2.8 million in two driver accidents, for a total of 2.8 million accidents.
	Per the NHTSA http://www.nhtsa.dot.gov/people/economic/ecomvc1994.html the economic cost of motor vehicle crashes in 1994 was $150 billion.
	National Safety Council http://www.nsc.org/lrs/statinfo/af78.htm economic cost of motor vehicle crashes in 1997 was $200 billion.

Copyright @ 2010 by Fathers' Manifesto & Christian Party