Look Both Ways with David & Wes

By Wes Marshall & David ZipperScience Education Leisure Automotive

Look Both Ways with David & Wes episodes

October 15 Episode 32: Gas Prices + Who Really Pays for Our Roads?
Gas Prices - David & Wes talk about high gas prices and whether the changes they prompt will stick. Some people try transit or bicycling. Others start shopping for an EV or a hybrid. But what happens when gas gets cheaper again? The conversation then turns to the shrinking value of fuel taxes as well as a question that many people think they already know the answer to: who pays for our roads? Sure drivers contribute through gas taxes, tolls, and fees, but that doesn't come close to covering the bill...
Topics include:
🔹 David's trip to London
🔹 Gas tax holidays & if they help the cause
🔹 Oregon’s pay-per-mile program & whether road usage charges are a better way forward
🔹 The future of the federal gas tax
🔹 The myth that drivers pay for roads
Subscribe for biweekly conversations about all things transportation.
Additional resources:
U.S. Cities See Public Transit Use Grow as Fuel Prices Remain High
America’s Hybrid Hype Has Hit the Used Market
Music by Charlie Van Stee
(courtesy of bensound)
Email us at [email protected] or find us at www.lookbothwayspodcast.com, www.davidzipper.com, and www.wesmarshall.org

1 hr 13 min
October 01 Episode 31: Climate Week, Waymo + Is There a Role for Regional Rail?
Climate + Transportation - David & Wes kick things off with a good conversation about the irony of Waymo sponsoring Climate Week events. Electric robotaxis may be cleaner than gas-powered car trips, but that does not mean they help the bigger cause. The harder questions are about what kinds of trips they replace, whether they create new vehicle miles, and whether AVs reduce driving or simply make car travel easier to justify. From there, the discussion turns to regional rail and the role it could play.
Topics include:
🔹 Our most miserable travel experiences
🔹 Waymo, Climate Week, & the greenwashing question
🔹 Electric AVs & the problem of more vehicle miles
🔹 Colorado’s growing interest in regional transit & passenger rail
🔹 And send your Look Both Ways sticker ideas to [email protected]
Subscribe for biweekly conversations about all things transportation.
Additional resources:
Self-driving cars would be a climate disaster (David's article)
Music by Charlie Van Stee
(courtesy of bensound)
Email us at [email protected] or find us at www.lookbothwayspodcast.com, www.davidzipper.com, and www.wesmarshall.org
1 hr 14 min
September 19 Episode 30: Speed Limits + Should Robotaxis Have to Follow the Law?
Speed Limits - David & Wes talk about speed limits: what they can do, what they can’t do, and the surprisingly complicated question of how robotaxis should handle them. Japan is moving toward lower speed limits on a large share of its roads, shifting many streets from 60 km/h to 30 km/h. That sounds simple enough, but speed is never just the number on the sign. It looks different from behind the windshield, in the crosswalk, inside a traffic study, or at the moment of impact. From there, David & Wes get into the 85th percentile, why traffic engineering has often treated driver comfort as data, and whether AVs should strictly follow the law, move with traffic, or behave the way human drivers actually do.
Topics include:
🔹 Car commercials that made us mad (or happy)
🔹 Why speed feels different from inside and outside the car
🔹 The 85th percentile trap
🔹 Robotaxis, speed limits, and the weirdness of legal compliance
🔹 And send us your Look Both Ways sticker ideas!
Subscribe for biweekly conversations about all things transportation.
Additional resources:
How Japan Won its ‘Traffic War’ (David’s article in Bloomberg)
Japan halves speed limit to 30km/h on all narrow city streets
Saturn “Sheet Metal” commercial from 2003
Everybody loves the Ford Ranger commercial from 1995
GM “Stop pedaling…start driving” advertisement from 2011
Dodge Charger Empty Streets Superbowl commercial from 2018
Nissan Sentra “Bob” commercial from 1990
VW “Think Small” commercial from 1959
Volkswagen 0-60? Yes. advertisement from 1998
Music by Charlie Van Stee
(courtesy of bensound)
Email us at [email protected] or find us at www.lookbothwayspodcast.com, www.davidzipper.com, and www.wesmarshall.org
58 min
September 17 Episode 30: Speed Limits + Should Robotaxis Have to Follow the Law?
Speed Limits - David & Wes talk about speed limits: what they can do, what they can’t do, and the surprisingly complicated question of how robotaxis should handle them. Japan is moving toward lower speed limits on a large share of its roads, shifting many streets from 60 km/h to 30 km/h. That sounds simple enough, but speed is never just the number on the sign. It looks different from behind the windshield, in the crosswalk, inside a traffic study, or at the moment of impact. From there, David & Wes get into the 85th percentile, why traffic engineering has often treated driver comfort as data, and whether AVs should strictly follow the law, move with traffic, or behave the way human drivers actually do.
Topics include:
🔹 Car commercials that made us mad (or happy)
🔹 Why speed feels different from inside and outside the car
🔹 The 85th percentile trap
🔹 Robotaxis, speed limits, and the weirdness of legal compliance
🔹 And send us your Look Both Ways sticker ideas!
Subscribe for biweekly conversations about all things transportation!
Additional resources:
How Japan Won its ‘Traffic War’ (David’s article in Bloomberg)
Japan halves speed limit to 30km/h on all narrow city streets
Saturn “Sheet Metal” commercial from 2003
Everybody loves the Ford Ranger commercial from 1995
GM “Stop pedaling…start driving” advertisement from 2011
Dodge Charger Empty Streets Superbowl commercial from 2018
Nissan Sentra “Bob” commercial from 1990
VW “Think Small” commercial from 1959
Volkswagen 0-60? Yes. advertisement from 1998
Music by Charlie Van Stee
(courtesy of bensound)
Email us at [email protected] or find us at www.lookbothwayspodcast.com, www.davidzipper.com, and www.wesmarshall.org
58 min
September 03 Episode 29: Older Drivers + Who Wants to Drive Forever?
Senior Mobility - David & Wes talk about older drivers, road safety, and the uneasy idea of “driving forever.” Wes starts with a paper he co-authored about how people think about driving, aging, and the possibility that they may someday need to give up the keys. But the point is not just what happens when someone can no longer drive; it is what happens before that. David then talks about visiting his parents’ retirement community, where slow streets, golf carts, and walkable destinations offer one version of what can come after driving becomes less central. But even there, the tradeoffs are real (and one neighbor bought a Tesla hoping Full Self-Driving might help him keep going). That opens up a bigger conversation about safety, independence, loneliness, family, and what life after driving can actually look like.
Today's topics:
🔹 The Fiat Topolino
🔹 Transportation stories about our grandparents
🔹 Our first Look Both Ways merch, which is going to be sticker-focused... and to start, we’re holding a sticker idea contest so send your suggestions to [email protected] (and we’ll put the best ones up for a listener vote)
Subscribe for biweekly conversations about all things transportation!
Additional resources:
Fiat Topolino Officially Goes on Sale in the U.S. for Under $15K
Who wants to drive forever? Exploring attitudes toward driving and aging (Wes's paper with Dan Piatkowski)
Music by Charlie Van Stee
(courtesy of bensound)
Email us at [email protected] or find us at www.lookbothwayspodcast.com, www.davidzipper.com, and www.wesmarshall.org
1 hr 5 min
August 20 Episode 28: The Global Road Safety Gap + Why the U.S. Is Falling Behind
Global Road Safety - David & Wes take a global view of road safety and ask why the United States keeps falling behind. They start with the U.S. being the only country to vote against a United Nations road safety declaration, then turn to a more uncomfortable comparison: the U.S. now appears to have a worse per-capita road fatality rate than Russia. From there, they look at the widening global road safety gap, including countries that once had worse safety records than the U.S. but have since lapped us. They also talk about Pontevedra, Spain, a city that dramatically reduced car dominance and has not had a road fatality since 2011.
Today's topics:
🔹 Why the U.S. voted against a global road safety declaration
🔹 How Russia’s road safety record compares to the U.S. over time & countries that used to be more dangerous than the U.S. but are now far safer
🔹 Why “car-free” cities like Pontevedra still have cars
🔹 Monster truck rallies, obviously
Subscribe for biweekly conversations about all things transportation!
Additional resources:
This Spanish city has been restricting cars for 24 years. Here’s what we can learn from it. (David's article in Fast Company)
The U.S. Alone Votes Against A Road Safety Declaration
Digger's Dungeon (Home of the Gravedigger)
Music by Charlie Van Stee
(courtesy of bensound)
Email us at [email protected] or find us at www.lookbothwayspodcast.com, www.davidzipper.com, and www.wesmarshall.org

1 hr 9 min
August 06 Episode 27: The Federal Transit Funding Freeze-Out + Bike Lanes Under Threat
Transit Funding Freeze - David & Wes dig into our frozen federal transit funding situation and what happens when major transit projects are not officially killed, but also are not allowed to move forward. After new reporting on the Trump administration’s apparent halt in final agreements for Capital Investment Grants, they talk about what these delays mean, why stalled transit funding makes projects more expensive, and the hard reality that cities can no longer assume the federal government will be a reliable partner.
Other topics:
🔹 Lebron’s new commute
🔹 FHWA’s Proven Safety Countermeasures website & the disappearance of road diets and speed safety cameras
🔹 Bicycling disappearing from FHWA’s proven safety countermeasures, along with the infrastructure that helps make biking safer
🔹 Why Waymos are still blocking bike lanes (and what to do about it)
🔹 We also answer a couple mailbag questions and, for some reason, talk more about Fabio
Subscribe for biweekly conversations about all things transportation!
Additional resources:
Congress Budgeted Billions for Big Transit Projects. Trump Isn’t Spending It.
FHWA's Proven Safety Countermeasures website
Why Are Waymos Still Blocking Bike Lanes? (David's article in The Driverless Digest)

Music by Charlie Van Stee
(courtesy of bensound)
Email us at [email protected] or find us at www.lookbothwayspodcast.com, www.davidzipper.com, and www.wesmarshall.org

1 hr 4 min
July 23 Episode 26: Tire Pollution Is Not Just a Salmon Problem + The Takes We’re Taking Back
Tire Pollution - David & Wes look at tire pollution and why the harms may be broader than most people realize. What started as a story about 6PPD-Q washing into streams and devastating coho salmon is now raising new questions about human health, including a recent study linking tire-related pollution to Alzheimer’s-related pathways. They talk through what we know, what we still do not know, and why tire wear should be part of the transportation pollution conversation, even in a world with more electric or autonomous vehicles.
Other topics:
🔹 What we unexpectedly learned about each other over the last year
🔹 David revisits Abundance & why his thinking has changed
🔹 Wes revisits traffic cameras & why his thinking has changed
Subscribe for biweekly conversations about all things transportation!
Correction: The Institute for Progress (rather than the Institute for Fiscal Progress) published The Transit Abundance Playbook
Additional resources:
EVs Are Sending Toxic Tire Particles Into the Water, Soil, and Air (David's article in The Atlantic)
Learning What Substance Is Suspected of Causing Alzheimer’s May Throw You Into an Existential Crisis (Futurism)
Tire chemical responsible for killing coho salmon in urban streams (U. Washington study)
There’s a Big Problem With Your Car’s Tires (Slate)
Music by Charlie Van Stee
(courtesy of bensound)
Email us at [email protected] or find us at www.lookbothwayspodcast.com, www.davidzipper.com, and www.wesmarshall.org

1 hr 4 min
July 09 Episode 25: How Stressful Is Your Bike Ride? + Bike Lane Camera Enforcement
Bike Stress - David & Wes talk about bike route stress and a major blind spot in the existing Level of Traffic Stress method: intersections. The current approach does a good job rating street segments, but it largely ignores exactly where a route can become far more stressful in real life. David & Wes discuss a new survey designed to help fix that gap by bringing intersections into the mix, and why better bike safety analysis depends on measuring the full route, not just the links between intersections.
Other topics:
🔹 The bike tours we wish we could take (or not)
🔹 Bike lane cameras & whether automated enforcement could/should keep bike lanes clear
🔹 Some fun mailbag questions from listeners
Subscribe for biweekly conversations about all things transportation!
Links to the survey:
Bicyclist Intersection Stress Survey
https://ucdenver.co1.qualtrics.com/jfe/form/SV_3ZS9DLyszX7GnYO?Q_CHL=qr
Additional resources:
Another Year of Devastating and Preventable Bicyclist Deaths
A New Tool in the Battle to Keep the Bike Lane Clear (David’s article in Bloomberg)
Don’t Park in the Bike Lane! Santa Monica Started Issuing Automated Bike Lane Tickets Today
Pittsburgh Stationary Automated Curb Enforcement
Music by Charlie Van Stee
(courtesy of bensound)
Email us at [email protected] or find us at www.lookbothwayspodcast.com, www.davidzipper.com, and www.wesmarshall.org
1 hr 10 min
June 25 Episode 24: Crash Data Blind Spots + Who Gets to Use Public Roads?
Crash Data Blind Spots - David & Wes dig into crash data and why Americans may know less about road deaths than we think. Everyone says they want data-driven safety policy, but the data we rely on often miss major categories of harm, including crashes on private property, parking lots, driveways, and behind gates. They talk through what gets counted, what gets left out, and why police-collected crash data can turn a partial record into something that looks more complete than it really is. It’s a conversation about why better road safety depends not just on having data, but on understanding where that data comes from, who collects it, and what it fails to see.
Other topics:
🔹 Our first jobs
🔹 The implications of a city turning public streets into a gated community
🔹 Fabio
Subscribe for biweekly conversations about all things transportation!
Additional resources:
Bow Mar’s plan to install a gate to reduce traffic has Denver, Littleton ready to retaliate
Waze Hijacked L.A. in the Name of Convenience. Can Anyone Put the Genie Back in the Bottle?
Gordon S. Wood, Pioneering Historian of Early America, Dies at 92
NHTSA's Non-Traffic Surveillance (NTS)
Music by Charlie Van Stee
(courtesy of bensound)
Email us at [email protected] or find us at www.lookbothwayspodcast.com, www.davidzipper.com, and www.wesmarshall.org
1 hr 4 min