Q I saw a police car ducking and dodging its way through traffic. The officer was driving almost Code 3 but without red lights and siren. Other drivers were caught unaware and didn't know how to react. When it passed, the rear amber lights were flashing, but that was all.

I think the state vehicle code rules that red lights mean pull out of the way. What is the legal thing to do when seeing this kind of police driving?

Patrick Bellomi

A Slow down and move to the right if you can. Officers should generally use red lights and sirens when responding to an emergency to exempt themselves from the rules of the road. But sometimes, depending on the situation, a siren could alert a suspect and make a dangerous situation worse.

San Jose police have a policy that all officers are supposed to follow all traffic laws unless responding to an emergency or trying to apprehend a suspect. Vehicles engaged in an emergency operation are generally required to use both the red lights and siren. When either the red light or siren has been discontinued, emergency operation of the vehicle should stop and all speed and traffic laws should be observed.

But there are times when the rules don't apply, such as when officers are pacing other drivers to determine speed, or conducting surveillance on a suspect vehicle. If using red lights or siren would endanger the officer or tip off a suspect and help that person flee, then the officer need not use them.

Flashing rear amber lights are usually used to alert other drivers that the officer is answering a call.

Q I am uncertain about what to do when I approach a school bus with its lights flashing and the stop sign out. I always stop and wait until the lights stop flashing and the stop sign is pulled in, usually with my emergency flashers blinking. Other cars stop, but then continue. Which is correct?

Ken Crook

San Jose

A It depends on the layout of the street. Here are the rules if a bus has its flashing red lights turned on and its stop arm extended:

  • When on a street with one lane in each direction, all drivers must stop when overtaking a school bus from either direction.

  • Drivers in all lanes traveling in the same direction as a stopped school bus must always stop.

  • A driver in the opposing direction need not stop on a divided highway with an island or with two sets of solid double yellow lines at least 2 feet apart or on any multilane road consisting of two or more lanes in each direction.

  • If a bus driver holds up a stop sign and walks students across the street, all drivers must stop.

    Q I was parked on Mission Street near San Pedro when a San Jose police officer went through a red light. He stopped at the next light, indicating that he was not in hot pursuit of someone. The light changed and he left. Could I have made a citizen's arrest because his actions were illegal?

    B.M.

    Los Gatos

    A No, but here's what you can do if you see an officer driving in an unsafe manner. Report it to the Police Department and try to include the vehicle number, time of day and place where you saw this.

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