States Look to Lower Speed Limits

By Douglas Shinkle and Jonathon Bates | Vol . 30, No. 3 | January 2021


Speeding has been a persistent public safety issue for decades and the subject of attention from federal, state and local governments. Speeding-related crashes have accounted for more than 25% of annual crash deaths since 2008, according to the National Highway Traffic Safety Administration (NHTSA). NHTSA considers a crash to be speeding-related if the driver was charged with a speeding offense or if a law enforcement officer indicated that racing, driving too fast or exceeding the posted speed limit contributed to the crash. In 2019, 9,478 deaths, or 26%, of all motor vehicle fatalities, occurred in speed-related crashes.

A few miles per hour can be the difference between life and death, especially for vulnerable road users such as pedestrians. A study published by AAA in 2011 examined vehicle speeds when they crashed into pedestrians and found that 10% of pedestrians died when hit by vehicles traveling at 23 mph. But that figure increased to 25% if the car was going 32 mph, 50% at 42 mph and 75% at 50 mph. And, at 58 mph, 90% of pedestrians died.

AAA’s 2019 Traffic Safety Culture Index reported that 64% of surveyed drivers considered speeding over 10 mph on residential streets to be extremely or very dangerous. However, about 41% of drivers reported doing so within the past month.

State Action

Over the past decade, at least 10 state legislatures―in Colorado, Hawaii, Indiana, Massachusetts, Michigan, Minnesota, Montana, New Hampshire, Oregon and Washington—have given state and local governments more flexibility to lower speed limits. And at least six states—Georgia, Maryland, New Jersey, New York, North Carolina and Tennessee—have enacted specific authority for certain municipalities to lower speed limits.

Laws passed in recent years in Oregon and Washington permitted all localities to establish maximum speeds on local roads that are lower than the state’s maximum speed limit. Washington’s bill, signed into law in 2013, enabled localities to determine safe maximum speeds, including decreasing the limit at intersections and decreasing the limit to not less than 20 mph. Seattle has taken advantage of the law to lower speed limits on neighborhood greenways, which are residential streets that prioritize travel by bike and foot and often include other traffic-calming attributes. Oregon passed legislation in 2019 allowing local governments to reduce speed limits by 5 mph on highways, provided they are not arterial highways, that are located in residential districts. The Oregon legislature had previously given Portland such flexibility in 2017, and the city responded by creating a 70-mile network of neighborhood greenways with 20 mph speed limits.    

The New York Legislature passed a law in 2014 to give New York City the authority to lower citywide speeds by 5 mph to 25 mph. Citing a 300% spike in fatalities in July 2020 over the same month in 2019, city officials announced they would be expanding the lower 25 mph speed limit to eight additional streets.

Massachusetts enacted a law in 2016 authorizing localities to set speed limits at 25 mph in certain instances, with Boston, Cambridge and Somerville doing so thus far. In Boston, the default speed limit is now 25 mph, unless signage states otherwise. The Insurance Institute for Highway Safety (IIHS) undertook a study in 2017 to compare average speeds in Boston with Providence, R.I., where the speed limit remained 30 mph. Similar roads, including a mix of arterial, collector and local roads, were examined. According to the IIHS study, there was a 29.3% decline in the odds of vehicles traveling faster than 35 mph in Boston. In addition, the odds of vehicles going faster than 30 mph fell by 8.5% and the chance a vehicle would exceed 25 mph declined 2.9%.

The Twin Cities of Minneapolis and St. Paul, Minn., took advantage of a law passed in 2019 to lower their speed limits on certain roads by 10 mph to 20 mph on most city-owned residential streets. The Michigan Legislature enacted a 2019 law authorizing, until Jan. 1, 2024, speed limits of 25 mph on highway segments that are part of the local street system and within land zoned for residential use, if approved by the state’s Transportation Commission.

Montana tackled higher speed roads with 2019 legislation that expanded the state’s ability to establish special speed zones. Previously, such zones had to be less than 50 miles in length, but the new law allows these zones on highway corridors with increased crash frequency or fatal crashes. Another 2019 Montana bill gave county commissioners more latitude to set school zone speed limits, provided the limit is no lower than 15 mph.