50mw green laser problem

hi.

A friend of me has a problem with the police. last night he shined with his pointer in a small flat. After he decides to stop the "lasering" the police stand before his door. the police said that the man in his flat he shined at had a red eye with water. I thought : is that possible ? i mean the flat was nearly 120m away and the divergence is big. so when the is not bundled can it cause something like this ? the firest the he had (next day the laser goggles came) he shined accidentally in his eyes and nothing happened. so what do you think ?

50mW (if it really was 50mW) can permanently damage eye, even after 120m, but that really depends on divergence. It is however common that divergence is good enough even for cheap pointers. The damage would be on the 'lower scale' though, most likely not detectable without proper eye examination.
As for red eye .. could be, such reactions are different for each person. But it is entirely possible.

But generally you never shine lasers at people, or places where there can be, much less class IIIB and higher.

totally impossible