A video explainer of the notorious traffic law that explains why some cities have to raise speed limits to enforce traffic safety.
To understand the scale of the challenge that must be overcome to achieve Vision Zero safety goals to eliminate traffic fatalities and to break the strangle hold cars have on U.S. cities, look no further than the 85th Percentile Rule, as neatly explained in the Grist video shown above.
For more background, see past Planetizen coverage of the 85th Percentile Rule.
FULL STORY: A 1930s city planning rule has drivers setting their own speed limits

Alabama: Trump Terminates Settlements for Black Communities Harmed By Raw Sewage
Trump deemed the landmark civil rights agreement “illegal DEI and environmental justice policy.”

Study: Maui’s Plan to Convert Vacation Rentals to Long-Term Housing Could Cause Nearly $1 Billion Economic Loss
The plan would reduce visitor accommodation by 25% resulting in 1,900 jobs lost.

Planetizen Federal Action Tracker
A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

Wind Energy on the Rise Despite Federal Policy Reversal
The Trump administration is revoking federal support for renewable energy, but demand for new projects continues unabated.

Passengers Flock to Caltrain After Electrification
The new electric trains are running faster and more reliably, leading to strong ridership growth on the Bay Area rail system.

Texas Churches Rally Behind ‘Yes in God’s Back Yard’ Legislation
Religious leaders want the state to reduce zoning regulations to streamline leasing church-owned land to housing developers.
Urban Design for Planners 1: Software Tools
This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.
Planning for Universal Design
Learn the tools for implementing Universal Design in planning regulations.
Caltrans
Smith Gee Studio
Institute for Housing and Urban Development Studies (IHS)
City of Grandview
Harvard GSD Executive Education
Toledo-Lucas County Plan Commissions
Salt Lake City
NYU Wagner Graduate School of Public Service