Four-Way Stop, an Oncoming Left-Turner and a Siren Behind You
It is 8:10 a.m. in a residential part of Brandon. You are southbound on a two-lane street approaching a four-way stop and you have just stopped at the line. A car approaching from your right, westbound, is already stopped at its sign. Directly opposite you, a northbound car arrived about two seconds before you did and is signalling left. You intend to go straight through. A pedestrian walking a dog is crossing on your left, still about four steps from reaching your lane. A parked car sits tight against the curb on your right, and a plowed snowbank narrows the corner on your left. Just as you start to release the brake, a siren rises behind you: an ambulance is about 60 m back in your lane, lights flashing, closing quickly.
1. What is the first thing you do, and what are your options if you cannot move right?
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The ambulance takes priority over every right-of-way question at the stop sign. You must not enter the intersection in front of it, even though it is technically your turn, because an emergency vehicle with lights and siren has the right of way and your crossing would put you in its path or force it to brake. First choice is to clear its lane: signal right, ease as far to the right as the parked car allows, and stop. If the parked car and snowbank leave no room, stay put and let the ambulance find its way around or past you; a predictable stopped vehicle is easier to work around than one that lurches unpredictably. Do not drive onto the sidewalk or into the snowbank, and do not wave the ambulance through. Once it has passed, re-check the whole intersection, because the other drivers may have reacted to the siren and moved out of turn.
2. After the ambulance clears, in what order does traffic proceed, and why?
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The pedestrian goes first. They are already in the crosswalk, and a pedestrian in a crosswalk has the right of way regardless of vehicle arrival order, so you wait until they and the dog are clear of your lane. Then the westbound car goes, because it was stopped at the line before anyone else and a four-way stop runs on first-come, first-served. After that, the contest is between you and the oncoming car signalling left. You are proceeding straight, so the left-turning driver must yield to you; a left turn crosses oncoming traffic and carries the burden of yielding. Confirm the oncoming driver has actually seen you and is waiting, rather than assuming, and only move once you have eye contact or the vehicle is clearly stationary. If you both hesitated and the oncoming car began its turn, let it complete rather than accelerating into a conflict.
3. Suppose the westbound car had arrived at exactly the same moment you did. How would that change things?
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When two vehicles reach a four-way stop at genuinely the same time and both want to go straight, the tie-breaker is yield to the right. The westbound car would be on your right, so it goes first and you wait. That rule exists because it gives both drivers a single, predictable answer instead of a standoff or a guessing game about who is being polite. In practice, simultaneous arrival is often ambiguous, so the safer approach is to watch the other vehicle's wheels and body language rather than assuming your reading of the timing is correct; if the other driver starts moving, let them. The tie-breaker never overrides the pedestrian in the crosswalk or an emergency vehicle, so the pedestrian still crosses first and the ambulance still passes before either car enters the intersection.