@AviK
#1 Depends on Jurisdiction
In many jurisdictions the judge makes the defendant rise and questions whether he/she agrees to the guilty pleas and understands the ramifications. If the defendant says no, the judge may refuse the plea. Judge can order a court psychiatric evaluation
#2 Morality is a set of beliefs, often personal or religion based. In US legal system Ethics are a set of rules that Attorneys and Judges must follow or be subject to sanctions.
#3 A judge in charging the jury will remind them that the attorney’s summation is NOT evidence, and has not been given under oath, subject to cross examination and penalties of perjury