Are there laws or statutes governing the directing of traffic by citizens or "members of the public"?

A scenario I often encounter is one in which someone — typically another rider or pedestrian in a group that has stopped or slowed at road crossing — will signal an approaching driver to proceed across the flow of bicycle traffic. I realize that people who do this are trying to be helpful or courteous to the drivers, but they do so on behalf of others with whom they have not consulted and who they may not be aware of.

In particular, I'm wondering what the laws are in Massachusetts, though any information about New York City, London, Seattle and Vienna or other areas would be welcome.

Is someone who does this liable in any way for any accidents that might ensue? Are they legally permitted to direct traffic in this way? Do they assume any responsibility for others who may become involved in the consequences of their "traffic direction" (given that those others generally have no idea that such directions have been given)?


4 Answers 4


Legally permitted to direct traffic (with force of law), no, not anywhere I'm aware of. That's a state/police reserved power in all cases I can think of.

Could someone do that in an advisory capacity, sure. Are they opening themselves up to liability. Yep. Very much so. Especially since there's no requirement that anyone follow their directions (thus they may appear to be offering "safe crossing" when they have no legal basis to be able to guarantee it).

Don't do it, and use great caution when around people that are doing it.


Yesterday afternoon during Friday rush hour, I came upon a 2 car head on collision at a blind curve in my area. I am a hospital employee and have training in emergency response so I stopped to help when I saw a young man clutching his eye.

I put on my poncho and did my best to make clear signals to drivers. All the participants were physically fine, but there was a heavy rain and if I hadn't acted, I suspect there would have been a 2 hour line of traffic at best or a series of further collisions at worst. There were no problems, and I left when the police arrived.

As I was leaving, a police officer thanked me but cautioned me that it was a legal liability. My thought on the matter is that if an accident had occurred, it would be because drivers ignored my signaling. So who knows who would be in trouble?

  • While we generally discourage anecdotes like this on Stack Exchange sites, this one illustrates both your point and the underlying ambiguity very well; thanks for sharing. Apr 21, 2012 at 16:34

My guess is that someone is potentially liable for providing incorrect "direction", though with two (well, three) caveats:

1 - The person taking the "direction" cannot generally absolve themselves from all responsibility.

2 - There may be "Good Samaritan" laws in effect that protect the "director" in some cases (most notably if doing something like directing traffic around an accident).

And --

3 - All of this goes out the window when you understand that, basically, anyone can sue anyone for anything, and you never can predict what a judge and jury are going to decide.


When I stop for a pedestrian at a crossing, I may hold my hand across the lane to stop cyclists behind me.

Signalling to others is probably legal IMO.

If I'm driving I'd like to take responsibility for my own conduct, and not drive into anyone no matter who or how anyone might signal at me. Every road I've driven on has clear right-of-ways, traffic lights, stops signs.

US law includes the notion of contributory negligence which may apply.

  • Interesting. I hadn't been looking at it from the driver's perspective. But you're right. I expect that though a driver might make the case that he was signaled to proceed, it was really his responsibility not to.
    – orome
    Oct 9, 2011 at 13:06

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