Is it illegal to have a dashcam recording constantly on public roads?

Nah, it's totally legal in most places to have a dashcam running on public roads - lots of people do it. Just check your local laws since a few places have privacy rules about audio recording, but video is pretty much always fine.

Depends on where you are, but in most places dashcams are totally legal on public roads. The main thing is audio recording - some countries and states have stricter rules about recording conversations without consent, so check your local laws if you're worried about that. Privacy laws vary a lot by region, so yeah, look up your specific country or state to be sure, but constant video recording in public is generally fine.

Most jurisdictions actually allow dashcams on public roads, so you're probably fine. The thing that trips people up is audio - depending on where you live, recording conversations (especially in two-party consent states/countries) can be way more restrictive than just video. I'd double-check your specific location's wiretapping or eavesdropping laws before you hit record, but visually documenting traffic is generally a non-issue.