Final answer:
Individuals like Michael Morton and Jean Gianini have been convicted of murder without a body, with developments in DNA evidence and psychological testing influencing some cases. Public opinion and legal procedures have also played roles in determining the outcomes of various historic trials.
Step-by-step explanation:
Convictions for murder without a body as proof can be complex and rare, but they have occurred. One notable case is that of Michael Morton, who was wrongfully convicted of the murder of his wife in 1986. He spent 25 years in prison before being exonerated by DNA evidence in 2011.
In another historical example, Jean Gianini was convicted in 1914 for the murder of his former teacher Lydia Beecher, and his sentence was influenced by psychological testing. The cases of Sacco and Vanzetti also highlight the conviction of individuals despite serious doubts about their guilt in the context of a reactionary climate towards immigrants in the 1920s.
Other instances point to procedural issues such as the case of Ernesto Miranda, where the Supreme Court’s focus was not on his actual guilt of the crimes but on the violation of his constitutional rights. Additionally, there are instances where the public regarded certain verdicts as unjust, such as the botched execution of a convict or when reactionary sentiments against specific social groups influenced the outcomes of trials.