Why do public buses have blue-tinted lights inside them?

Um its just a different kind of light, I don’t think it really makes a difference… if I’m positive I believe those are LED lights.

It’s so that you can’t see your veins if you’re planning on shooting up.

Why was my response moderated? The lights are blue to make it harder for drug users to see their veins, so that they can’t inject.

These lights are non-reflective on the windows. It’s mainly to allow the driver to see outside the bus, even while the bus is lit sufficiently for the passengers to see. If the lights were white, the driver would be able to see his own reflection in the windscreen and his view of the road would be impaired. In the UK buses have normal white lights upstairs and the blue ones downstairs.