On Feb. 3, 1956, highway speed limits of 65 mph by day and 55 by night went into effect in Michigan. Prior to this, it was up to motorists to determine what speeds were safe and reasonable.
In 1901, the first motor speed limits in the U.S. were established to improve traffic safety and reduce the risk of vehicle crashes. Connecticut started the trend, limiting the speed to 12 mph in cities, 15 in rural areas. Several states followed suit, including New York, which introduced the first comprehensive traffic code in 1903.
Across the nation, laws regarding speed continued to vary. As late as 1930, some states didn’t even require a license to operate motor vehicles.
The first federal speed limit law was passed in the 1970s in response to oil shortages. In January 1974, President Richard Nixon signed a national speed limit of 55 mph into law.
The availability of fuel and the cost of fuel resolved in the 1980s, and the national maximum speed limit on interstates increased to 65 mph.
In 1995, the U.S. Congress handed speed limit laws back to the individual states, allowing each state to decide its maximum speed to drive. Since then, 35 states increased their limits to 70 mph or higher.
In Michigan, speed limits are based on 85th percentile speed. This means the speed at or below what 85 percent of drivers currently drive on a given road section determines the speed limit. For example, if 85 percent of drivers on a section of road are driving 55 mph or less, the 85th percentile speed would be 55. The 85th percentile is the national standard for setting speed limits.
