Regarding the conviction of innocent people:

http://www.witchhunt.org


http://meltingpot.fortunecity.com/grenada/776/

Regarding prison rape and prison reform:

http://www.spr.org/

Regarding Police Brutality

http://www.policeabuse.org/

Regarding The Death Penalty

http://www.ncadp.org/

Ok. There's plenty more links in the death penalty thread....