Most spacecraft are launched and orbit prograde -- in the same direction that the Earth rotates -- to give a "speed boost" to get to orbital velocity. One would therefore expect that the trajectories of the debris caused by spacecraft collisions would not be truly random in all directions, but rather biased in prograde directions.
Has this actually been observed by those tracking orbital debris?
Inspired by this comment.
"What is the typical relative impact velocity of orbital debris in low Earth orbit?" is a somewhat similar concept, but the answers take a theoretical approach. I am asking for an evidence-based answer.
I am deliberately not tagging this kessler-syndrome, as I do not believe the effect depends on the density of orbital debris.