Question: what are controversial issues in psychology?
Answer: The Stanford Prison Experiment. ... 
The Milgram “Shock Experiments” ... 
The “Elderly-related Words Provoke Slow Walking” Experiment (and other social priming research) ... 
The Conditioning of Little Albert. ... 
Loftus' “Lost in The Mall” Study. ... 
The Daryl Bem Pre-cognition Study. ... 
The Voodoo Correlations in Social Neuroscience study.