Why did they allow him into the open in prison?
why not?
Because they have a resposibility to keep him as safe as reasonably possible.
I don't know much about prison policy, but from what I have gathered, "high profile" prisoners are often kept segregated from the general population. He was likely "supposed" to be segregated per the prison's responsibility to keep him safe (again, according to prison policy--not my personal beliefs). However, it's not surprising that they may have let him "wander" into general population.
His crimes had a race angle, too, of course. Then with the horrible disregard for those victims, I just can't see how a decision could be made to create such a risk for absolutely no benefit. Any prisoner in the vicinity of Dahmer, at any time, could get caught up in violence due to the situation. So it wasn't only Dahmer whose safety was jeopardized.
And SF, no, it was an official decision. He was out and about working (I believe) with other inmates when he was attacked by one.
Ahh, my mistake. Interesting. I wonder why he was not segregetated from general population.
I'll look into it. But from what I've heard, he might have requested the change. That could only mean he was delusional and (or) plain suicidal, which isn't a valid reason to grant him that crazy wish. To say nothing of the others who were put at risk by having him in the open.