[gambiting]

Tbf, even cars put the brake lights on based purely on deceleration nowadays in addition to triggering when the brake pedal is pressed. It's covered by legislation in both EU and US, since BEVS and PHEVs can have very aggressive regen braking, and the legislation basically says if your rate of deceleration is above X, then lights need to be on even if the brake pedal hasn't been pressed.

[jamiek88]

Yes and my Kia ev6 needed a software update to do that. I had a couple incidents where people were surprised by my deceleration before the update.

Now in regen the brake lights come on above a certain harvest level.

[Cthulhu_]

In addition, some cars - I don't know if this is legislated or a feature - will blink the brake lights or even the alarm lights if it detects a sudden hard brake (emergency brake). But people would do that themselves anyway if they for example had to slow down suddenly due to a traffic jam or whatever.