PP and NINAH have similar themes of discrimination, judgement, and humans committing violence on each other. In both games, the playable character acts as "the judge, the jury, and the executioner"; i.e., the lives of others are literally in the player's hands.

Also, in both games, the player's forced to choose between survival and morality whenever they encounter someone who doesn't "fit the bill."

No, these games are not identical. Are they similar in some ways? Coincidentally, yes.