Parking lights are for being PARKED

There isn't such legislation.

You are obliged to use headlight from half an hour after sunset, and up to half an hour before sunrise. That's what legislation says. There's noting about 5pm in it.

But how?

In the past cars by default didn't have any lights until you turned them on.

So you are saying that car design feature to include front DRL to make cars more visible at daytime is just stupid, because it doesn't include also rear light (which are useless at daytime in good weather).

Well if people are relying on front DRLs to be seen I think the same should be done on the rear. I dont see the big issue with having them on the back anyway. If anything there should be a front and rear light that comes on all the time

Yes, the engineers should have anticipated it and it is not good interface design. But that's the product they bought, so they should bloody well learn how to use it safely before they took it out on the road.

I wonder about the legality of some of fancy new LED lights. I saw a Land Rover or Range Rover where the rear indicator 'replaces' the red back light while the indicator is flashing. Is that legal, I wonder?

I agree, many manufacturers seem to making stuff up as they go along with regards to lighting, but especially in regard to indicators. It seems to be more about looking flashy and innovative rather than functionality IMO. Also many cars where the rear indicators are embedded within the main cluster and sometimes no bigger than a €2 coin, making them extremely difficult to spot.

Cars don't usually reverse towards you at 100km/h or more.

Having front lights (low beam headlights or daylight running lights) makes an approaching car much more visible thereby sigificantly reducing risk of a collision.

Even in daylight some colour cars can blend more into the bckground. Low beam or daylight running lights make the car more easily seen and at a greater distance.

Look who's getting condescending. I've been driving safely, likely for more years than you've been on the the planet and I know when side lights are properly used.

In very many cases, like a rain shower in the sun, "automatic" rear lights are not activated by the wipers, making it very difficult to see a car in the grey/white spray. Driving into low sun, you are very hard to see from behind, despite the car believing it to be bright out.

DRL's are permitted to have more diffusion than dipped beams, so that they appear brighter off-axis, and so are more easily seen by more road users who are not head-on. This is why DRL's can be blinding at night.

The logic (which I don't agree is totally applicable in Ireland, due to low sun conditions), is that brake lights are less obvious in the daytime, if rear position lamps were already on, so they tend not to be activated with DRL's in Ireland.

It's totally confusing, especially so when manufacturers use the same symbol for entirely different functions. If I was to sit you in a random rental car, you would literally need to spend 10 minutes reading pages in the manual to figure out if a given symbol meant that your lights were on. But people don't even know it, so they are oblivious that it's even an issue.

Even highly trained pilots as I mentioned earlier fell foul of an utterly confusing MCAS system. I wouldn't be surprised if similar number of people are killed each year worldwide due to misleading lighting controls - needs proper legislation fast IMO, and it should be retrospective to force manufacturers to give free upgrades to old cars. Lights on all the time, and they deactivate with ignition off, so no worry to drain a battery.

Except driving behind another car the closing speed is probably zero or near to it and as another poster pointed out having tail lights on in daylight can make brake lights less visible.

Turning out from a side road the closing speed of a car on the main road could be around 100km/h.

If a car is overtaking the closing speed could be around 200km/h.

Well I've seen plenty of cars on the nations roads driving with no rear lights on & that includes the Gardaí.

Fog lights are intended to let other people see you, so there is a big point in having them on.

These don't come on automatically in any vehicle. They must be switched on by the driver purposely and are often not controlled from the lighting stalk but by separate switches on the dash.

In foggy conditions they’re not.

Shine a light into fog and it just reflects back off the fog.

Parking lights at least on VWs I've had, put the side lights on one side of the car only, So when parked. The side to the road is lit.