H.R. 4661 amends title 49 to preempt state laws that require a human occupant in ADS-equipped commercial motor vehicles and to allow Level 4–5 ADS trucks to operate interstate without a driver on board or a remote driver. The act defines ADS and related terms per SAE J3016, and directs the Department of Transportation to issue implementing regulations.
It also directs a regulatory review to streamline certain CFR parts for ADS-equipped vehicles and to align safety technology rules with ADS operations. The bill further instructs agencies to consider expanding acceptable warning mechanisms, such as cab-mounted beacons, in interpreting regulations.
At a Glance
What It Does
Inserts a new Section 31140 authorizing interstate operation of Level 4/5 ADS-equipped CMVs without a human driver or remote driver; adds ADS definitions to Title 49; and directs DOT to issue implementing regulations.
Who It Affects
Interstate trucking fleets deploying ADS tech, ADS OEMs and service providers, and state regulators responsible for safety rules that could otherwise apply to driverless operation.
Why It Matters
Establishes federal preemption over conflicting state occupant requirements, clarifies ADS definitions, and sets a regulatory path to reduce cross-state friction—critical for scaling autonomous commercial trucking.
More articles like this one.
A weekly email with all the latest developments on this topic.
What This Bill Actually Does
The bill creates a clear federal framework for ADS-equipped commercial vehicles, focusing on Levels 4 and 5 that can operate without a human driver or a remotely located driver. It adds ADS-specific definitions to the code and directs the DOT to implement regulations that would govern how these vehicles operate in interstate commerce, including how regulations are applied to driverless operation.
The package also seeks to reduce regulatory friction by examining how federal rules from the CFR apply to ADS vehicles and by ensuring that safety technologies receive appropriate consideration within existing statutory frameworks. Finally, it instructs regulators to consider updates to guidance on warning devices, making cab-mounted beacons permissible under certain interpretations.
The overall aim is to accelerate deployment while maintaining a predictable, uniform federal standard that carriers and manufacturers can rely on across states.
The Five Things You Need to Know
The bill creates a new ADS operation provision enabling Level 4/5 CMVs to operate interstate without a human driver or remote driver.
It preempts state laws that require a human occupant in ADS-equipped CMVs to promote uniform nationwide standards.
DOT is directed to issue implementing regulations to support ADS deployment and safety.
Definitions for ADS, ADS-equipped vehicles, and Level 4/5 are anchored to SAE J3016 definitions.
Regulatory interpretations are updated to include cab-mounted warning beacons as permissible warning devices.
Section-by-Section Breakdown
Every bill we cover gets an analysis of its key sections.
ADS-operated CMV authorization and preemption
Section 2 adds a new subsection 31140 to Title 49, authorizing Level 4/5 ADS-equipped commercial motor vehicles to operate in interstate commerce without a human driver on board or a remote driver. It requires the Secretary of Transportation to issue implementing regulations and preserves a statutory construction that nothing in the subsection requires an ADS to be installed in a CMV. The section also expands the Title 49 analysis by inserting a new subsection 31140 and by adding the ADS operation term to the section 31132 definitions.
Definitions for ADS and driving levels
Section 2 adds definitions to 49 U.S.C. 31132, including: (12) ADS-equipped vehicle, (13) ADS, (14) Level 4, and (15) Level 5. These definitions bind interpretation for regulatory purposes, aligning ADS capabilities with SAE J3016 taxonomy and clarifying that automation level 4/5 implies full driving automation under defined conditions and not mere driver assistance.
Reducing regulatory obstacles to safe integration
Section 3(a) directs the Secretary to assess the applicability of CFR Parts 350–399 to ADS-equipped CMVs, using a 2019 proposed rulemaking as reference, with the goal of updating regulations to reflect driverless operation, including concepts like remote drivers or remote assistance. Section 3(b) prohibits regulations that unduly burden carriers operating ADS-equipped vehicles or discriminate against ADS operations. Section 3(c) adjusts safety regulation width calculations by excluding ADS technologies and equipment. (Together, these provisions create a more favorable path for ADS deployment by reducing regulatory drag and preserving flexibility for safety tech.)
Regulatory parity and safety technology flexibility
This subsection clarifies that federal rules should not unduly burden ADS operations and ensures that safety tech can be adopted without disadvantaging ADS-enabled CMVs relative to traditional vehicles. It also explicitly reframes the interaction between safety standards and emerging ADS technologies to avoid artificial barriers to adoption.
Regulatory interpretations and warning devices
Section 4 requires federal regulations to be interpreted as if cab-mounted warning beacons are permissible warning devices, aligning with an exemption application docketed in 2023. This narrows the regulatory gaps that might otherwise restrict certain ADS operations and supports explicit warnings in the cab vicinity.
This bill is one of many.
Codify tracks hundreds of bills on Transportation across all five countries.
Explore Transportation in Codify Search →Who Benefits and Who Bears the Cost
Every bill creates winners and losers. Here's who stands to gain and who bears the cost.
Who Benefits
- ADS-technology developers and OEMs who can scale commercial offerings across state lines under a uniform rule of law, reducing state-by-state compliance costs.
- Interstate motor carriers piloting or deploying ADS systems, who gain regulatory certainty and potential efficiency gains.
- Federal regulators and highway safety researchers who benefit from a clearer federal framework and data collection opportunities under uniform standards.
- Industry groups advocating for streamlined rules and predictable timelines for ADS deployment.
- State transportation departments that align with a clear national standard and reduce disparate regulatory enforcement.
Who Bears the Cost
- States and localities may face revenue or administrative shifts as preemption reduces some state-level occupant safety rules.
- Carriers and fleets must invest in ADS-capable vehicles and remote operation systems, including training and maintenance costs.
- Insurance and risk-management sectors will need to adjust to different liability and risk profiles associated with driverless operations.
- Regulators may incur transitional costs to rewrite or harmonize enforcement guidance and to monitor ADS deployments at scale.
- Remotely located drivers and remote-assistance service providers could face changes in contracting, licensing, or qualification expectations as fleets move to driverless operations.
Key Issues
The Core Tension
The central dilemma is balancing uniform federal preemption that accelerates ADS deployment with the need to preserve safe, state- and local-level policy autonomy and to manage workforce transitions as automation scales.
The bill creates a clear federal path for ADS deployment by preempting conflicting state occupant requirements and by outlining definitions and regulatory pathways. But several tensions remain: federal preemption may undercut state safety experiments or localized innovation; the precise safety and liability regime for driverless operations remains to be fleshed out in implementing regulations; and the economic and workforce impacts—such as displaced drivers and the cost of upgrading fleets—will require careful management.
The proposed rulemaking to align CFR parts with ADS operations will need rigorous stakeholder engagement and transparent timelines to avoid unintended consequences, including gaps in hours-of-service enforcement, remote supervision standards, and interoperability across carriers and platforms.
Try it yourself.
Ask a question in plain English, or pick a topic below. Results in seconds.