Does flashing high beams give police probable cause to stop a vehicle? Is it illegal to flash high beams to signal other cars? If police see you doing so is it a valid pretext for a traffic stop?
Generally yes, but it depends on both context and jurisdiction. For example, if you arrived from a different street segment at 4-way stop at the same time as another car, and give a flash to indicate "go ahead," that by itself is not likely to be sustained as sufficient to justify a stop. If you come up close behind another car and flash your high beams as part of aggressive driving (e.g. message "get out of my way") then that may form a key contribution to a justification for pulling you over for aggressive driving. Many states also prohibit use of high beams when other cars are around because they have a tendency to blind other drivers (and blinded drivers are more likely to be in an accident), so if the officer observes you committing that offense it would be probable cause to pull you over for that. Here's an example from NY State where flashing high beams, alone, did not provide probable cause for an officer to pull over a vehicle. NY's law about high beams blinding other drivers specifies that the high-beams have to interfere with the other driver's operation of the vehicle for it to be an offense. See also citations near the end of this decision, which says: The Court of Appeals has indicated: "The mere flashing of lights, alone, does not constitute a violation of the statute (see People v. Meola, 7 NY2d 391, 397 [1960]; People v. Hines, 155 AD2d 722, 724 [1989], lv denied 76 NY2d 736 [1990]; People v. Lauber, 162 Misc 2d 19, 20 [1994]). Also, if you are flashing the police car, the officer may think you are trying to get his/her attention for some reason and that you are initiating a traffic stop. However, do be careful. This driver in Texas flashed his high beams at another car (which turned out to be a police car) because he thought the other car had its high beams on (the officer says it was just a new car; at least two other drivers had apparently flashed the officer for the same reason). The officer then applied the same law that driver was concerned about, forbidding the use of high beams that blind others. The driver was tased, shot, and killed as the officer applied the instant death penalty for his offenses, and the penalty was ruled justified. A dead driver cannot practically contest that stop later on, even though the family might try. See also Headlight Flashing: Legality on Wikipedia.
Almost everywhere, in any circumstances, it is the driver's responsibility to operate their vehicle so as not to get in an accident. When two drivers collide, responsibility can be divided among them depending on the details. However, when a driver hits a stopped object (including another vehicle), it is always the driver's fault for not operating his vehicle safely. It is possible the other vehicle may also receive a minor parking ticket or similar infraction for stopping on a shoulder or other invalid place. But that citation will not do anything at all to relieve your responsibility to operate your car without hitting obstacles.
The apportionment of fault will be highly case specific, based on ordinary principles of negligence. In one example, the fault was apportioned with 60% of the fault to the late left turner and 40% of the fault to the driver advancing imprudently into the intersection on a green light. See Pierce v. ING Insurance, 2006 NSSM 31 (my annotations and emphasis): [11] I believe that Mr. Pierce [the left-turning driver] was late in entering this intersection. I do not accept that he could not have stopped on the amber which he asserts. However, I am not prepared to find that he is solely responsible at law for the collision. [12] As stated above, I am unable to conclude with precise exactitude which signal light was on when Mr. Pierce [the left-turning driver] entered the intersection. I can conclude that the amber light had ceased and the green light for Mr. Williams [the through driver] had turned on at some point prior to the collision. The intersection is a well known intersection and given Mr. MacKinnon’s evidence of the relative speed of Mr. Pierce’s vehicle and what I understand to be the distances involved, I cannot accept that the signal light was green and turned to amber as Mr. Pierce entered the intersection. [13] On the other hand I am struck by two inescapable facts. First, the fact that Mr. MacKinnon who was stopped next to Mr. Williams did not proceed through the intersection because he knew it would not be safe to do so. While to some extent I take Mr. Boyte’s point that Mr. MacKinnon was, because of his experience with the intersection “hyper aware” to the prospect of drivers being late, I cannot entirely dismiss the fact that he obviously exercised prudence in not proceeding. The fact that Mr. Williams did not see Mr. Pierce’s vehicle is not an answer. In fact, just to the opposite in my view. [14] In my opinion, there is clear a duty on drivers stopped at an intersection to ascertain that the intersection is clear before proceeding once a light turns from red to green. Had Mr. Williams discharged this duty, the collision could well have been avoided. Your scenario is even more stark—not just a single late left turner, but an entire line of late left turners, readily apparent as an obstacle to safe advance. I would not be surprised if a judge were to attribute even more than 40% fault to the driver entering on the green. The Court of Appeal for British Columbia has even said (Pirie v. Skantz, 2016 BCCA 70, para. 14): ... where a through driver ... should have become aware of the left-turning driver’s own disregard of the law in circumstances that afforded him a sufficient opportunity to avoid the accident through the exercise of reasonable care, the through driver may be found wholly or primarily at fault for the accident.
"I don't know" is a better answer than most, but you should only say that if it's the truth. The three most important rules to follow when being questioned by a police officer are as follows: Do not lie. Do not incriminate yourself. Be cooperative (to the extent that you're not lying or incriminating yourself). "Do you know why I pulled you over?" or "Why do you think I stopped you?" are perfect opening questions for law enforcement to ask because there is no good answer. Any answer you give puts you at a disadvantage for the rest of the stop because you've tacitly accepted the officer's assumption that you did something wrong. The best response would be to simply reply back with their own question. "Why did you pull me over, officer?" If you say it right, it's rational, polite, and cooperative without actually answering anything. Your position from the very beginning should be that you did nothing wrong (even if you know that you did). It's the officer's job to make the case. It's not your job to help them.
An affirmative defense is a way of avoiding conviction by acknowledging you did the act claimed, but that such act was among the exceptions provided by the law which makes such acts otherwise an offence. That is, you affirm (acknowledge, admit) your action of using the device, but you are claiming that your use of the device (handsfree as a GPS guide) is okay, and therefore you should not be convicted. For all intents and purposes in this situation, your "2" and "3" are the same thing. The device is supported by something other than you holding it, and you are able to keep both hands on the wheel while using it in this way. Finally, a plain language reading of the definition for "hands-free accessory" suggests that using an object in the car to support the device where it can be seen, or using a feature of the device that speaks directions which you can hear, neither of which requires moving your hands off the wheel, will be considered such an accessory. It is also worth pointing out that such usage of a device (placed in a cradle or on the dashboard or turned up so it is heard) will be well-known to the legislators, and there is a reasonable interpretation of the law that would allow such usage. If this ever went to court, and somebody used this defence for this situation, they would probably be okay.
This is a deescalation tactic. By giving some ridiculous far out reason, the officer hopes to distract you from any combative or aggressive feelings you have about being stopped. You can do this too, if someone you think is getting progressively angrier might try and hurt you, bringing up something random forces their mind off their anger, even just for a moment. And sometimes, that's enough to avoid a conflict. As for the legality of telling you the reason, no they are not required to tell you the reason, as has been mentioned several times on stack exchange. If an officer says to himself, "I think this guy has crack on him because of X," and it's captured on his body cam, then he's covered. He can prove to the court that he did have reasonable suspicion to detain you, even if he later tells you, "I have a report of zombies in the area and I need to see your ID to determine if you have a death certificate."
Unlikely, but specific facts may change this. The fact a vehicle gets the approval of the NHTSA and/or other safety regulatory bodies will probably mean that it already passed a certain level of safety testing, and any reasons for a recall will only surface after orders of magnitude greater sample and/or testing time. Therefore, the probability of causing endangering participants in traffic and others are negligible. The duty of notice will most likely be on the manufacturer under a product liability theory. Driving continuously and/or repeatedly after notice may be a different matter if it actually results in harming one — theoretically even oneself.
Maybe. In many but not all situations, the police have a certain latitude in how they charge an incident. In many but not all socieities, speeding is seen as less morally repugnant than, say, theft or tax evasion. &quot;Can happen to anyone, oops,&quot; the excuse goes. So a credible expression of remorse might cause the police officer to issue a caution or verbal warning instead of a ticket. Unless you are in a place where there is a grossly antagonistic relationship between the police and the citizens, or where the police department relies on fines for funding.