[TulliusCicero]

It's not an injustice inherently, it's just a moral hazard that may lead to injustice (or other poor behavior). E.g. I remember hearing about a city that, after implementing red light cameras, shortened the yellow time, thus technically increasing the number of people who ran reds and gaining revenue (at the expense of actual safety since short yellows are more dangerous).

[ascagnel_]

Some of the comments in the linked thread go into this, but nobody was able to provide hard evidence of short yellows.