Young Maryland Drivers: Before and After the New Graduated Driver’s License (GDL) System Cynthia A. Burch, MPH National Study Center for Trauma & EMS University of Maryland, Baltimore
Jan 03, 2016
Crash Patterns in Young Maryland Drivers: Before and After the New Graduated Driver’s License (GDL) System
Cynthia A. Burch, MPHNational Study Center for Trauma & EMS
University of Maryland, Baltimore
Maryland GDL System Effective July 1, 1999 with these
changes: 3-level licensing system
Learner’s Permit – min. age=15 yrs. 9 mos.
Valid for 1 year (up from 6 months) Hold for 4 months (up from 14 days)
conviction-free Begin practice log for supervised driving
Maryland GDL System 3-level licensing system
Provisional License – min. age=16 yrs 1 mo (up from 16 yrs)
Requires successful completion of Driver’s Ed for all ages (was only if under age 18)
Completed practice log with 40 hrs of supervised driving
Must be held for 18 mos (up from 12 mos) conviction-free
Maryland GDL System 3-level licensing system
Driver’s License – min. age=17 yrs 7 mos. (up from 17 yrs)
Now: must maintain 18 month conviction-free period prior to full license regardless of age
Then: could convert to full license if conviction free for past 12 months or at age 18 regardless of convictions
Pre- and Post- Law Crash Data were collected through the
Maryland Automated Accident Reporting System (MAARS)
Citation Data were collected from the Maryland Court System
Data for Licensed Drivers were collected through the Federal Highway Administration from the Maryland Motor Vehicle Administration
Pre- and Post- Law 2 years of data were collected pre-
law (1997 & 1998) and post-law (2000 & 2001)
For population figures and total number of licensed drivers, the average of 1997 and 1998 were used for pre-law and the average of 2000 and 2001 were used for post-law
Analysis Crash frequencies and rates were
compared among 16 and 20-24 year-old populations and licensed drivers
Citation frequencies and rates were compared for the 16 and 20-24 year-old populations and licensed drivers before and after GDL implementation
Total crashesPre-Law Post-Law % change
16 y/o 7,212 6,147 -14.8
20 y/o 7,723 8,992 +16.4
21 y/o 7,644 8,931 +16.8
22 y/o 7,384 8,686 +17.6
23 y/o 7,109 8,120 +14.2
24 y/o 7,005 7,538 +7.6
20-24 y/o
36,865 42,267 +14.6
PopulationPre-Law Post-Law %
change
16 y/o 68,906 72,416 +5.1
20 y/o 61,120 68,398 +11.9
21 y/o 59,088 63,904 +8.2
22 y/o 57,836 60,930 +5.3
23 y/o 58,276 59,148 +1.5
24 y/o 63,514 59,488 -6.3
20-24 y/o
299,834 311,868 +4.0
Crash Rates (per 1,000 population)
Pre-Law Post-law % change
16 y/o 104.7 84.9 -18.9
20 y/o 126.4 131.5 +4.0
21 y/o 129.4 139.8 +8.0
22 y/o 127.7 142.6 +11.7
23 y/o 122.0 137.3 +12.5
24 y/o 110.3 126.7 +14.9
20-24 y/o 122.9 135.5 +10.2
Number of Licensed Drivers
Pre-Law Post-Law % change
16 y/o 23,018 18,356 -20.2
20 y/o 44,734 48,096 +7.5
21 y/o 41,934 46,648 +11.2
22 y/o 43,009 47,188 +9.7
23 y/o 45,304 48,586 +7.2
24 y/o 47,759 50,014 +4.7
20-24 y/o
222,740 240,530 +8.0
Crash Rates (per 1,000 licensed drivers)
Pre-Law Post-law % change
16 y/o 313.3 334.9 +6.9
20 y/o 172.6 187.0 +8.3
21 y/o 182.3 191.5 +5.0
22 y/o 171.7 184.1 +7.2
23 y/o 156.9 167.1 +6.5
24 y/o 146.7 150.7 +2.7
20-24 y/o 165.5 175.7 +6.2
16 y/o Citation Information Pre-law
15,739 citations were issued to 16 y/o drivers throughout the state
This is a rate of 228.4 per 1,000 population and 683.8/1,000 licensed drivers
Post-law 12,995 citations were issued to 16 y/o drivers This is a rate of 179.4 per 1,000 population and
707.9/1,000 licensed drivers This shows a 17.4% decrease in citations
issued, a 21.4% decrease in the citation rate per population, but a 3.5% increase in the citation rate per licensed drivers pre- and post- law
Citations for 16 y/o Drivers
Pre-law – 66.5% for speeding 19.5% for failure to wear a seatbelt (primary
law in MD) 5.6% for failure to yield
Post-law – 71.0% for speeding 16.4% for failure to wear a seatbelt 5.1% for failure to yield
Citations to 16 y/o Drivers
Pre-Law Post-Law % change
Belt Use 3,065 2,137 -30.3
Failure to Yield
888 661 -25.6
Red Light Running
1,266 878 -30.6
Speeding 10,464 9,232 -11.8
16 y/o Citation Rates(per 1,000 population)
Pre-Law Post-Law % change
Belt Use 44.5 29.5 -33.7
Failure to Yield
12.9 9.1 -29.5
Red Light Running
18.4 12.1 -34.2
Speeding 151.9 127.5 -16.1
16 y/o Citation Rates(per 1,000 16 y/o licensed drivers)
Pre-Law Post-Law % change
Belt Use 133.2 116.4 -12.6
Failure to Yield
38.6 36.0 -6.7
Red Light Running
55.0 47.8 -13.1
Speeding 454.6 502.9 +10.6
20-24 y/o Citation Information Pre-law
248,571 citations were issued to 20-24 y/o drivers throughout the state
This is a rate of 829.0 per 1,000 population and 1,116.0/1,000 licensed drivers
Post-law 242,345 citations were issued to 20-24 y/o drivers This is a rate of 777.1 per population and
1,007.5/1,000 licensed drivers This shows a 2.5% decrease in citations
issued, a 6.3% decrease in the citation rate per population and a 9.7% decrease in the citation rate per licensed drivers pre- and post- law
Citations for 20-24 y/o Drivers
Pre-law – 56.0% for speeding 21.8% for failure to wear a seatbelt 1.1% for failure to yield
Post-law – 55.1% for speeding 21.0% for failure to wear a seatbelt 1.2% for failure to yield
Citations to 20-24 y/o Drivers
Pre-Law Post-Law % change
Belt Use 54,105 50,774 -6.2
Failure to Yield
2,808 2,946 +4.9
Red Light Running
22,845 18,045 -21.0
Speeding
139,087 133,522 -4.0
20-24 y/o Citation Rates(per 1,000 population)
Pre-Law Post-Law % change
Belt Use 180.4 162.8 -9.8
Failure to Yield
9.4 9.4 -
Red Light Running
76.2 57.9 -24.0
Speeding 463.9 428.1 -7.7
20-24 y/o Citation Rates(per 1,000 20-24 y/o licensed drivers)
Pre-Law Post-Law % change
Belt Use 242.9 211.1 -13.1
Failure to Yield
12.6 12.2 -3.2
Red Light Running
102.6 75.0 -26.9
Speeding 624.4 555.1 -11.1
Conclusions As the total number of crashes involving a
16 y/o driver decreased and the crash rate per population decreased, the crash rate per licensed drivers increased.
As the total number of citations issued to 16 y/o drivers decreased and the citation rate per population decreased, the citation rate per licensed drivers increased.
Similar results were found in a San Diego study presented at AAAM.
Discussion Previous studies have focused on the
number of crashes involving 16 y/o drivers and the population crash rate as a means of evaluating GDL systems.
One must also take into account the number of licensed 16 y/o drivers.
The decrease in population crash rate supports the decrease in crash frequency, but that does not translate into a safer driving environment.
Discussion Research needs to focus on crash and
citation rates in the associated population of licensed drivers, not the census population.
Driver education programs and required driving times need to be reevaluated to encourage safe driving habits among young drivers before they are issued full drivers licenses.
Additional Authors:
Patricia DischingerTimothy Kerns