All persons are capable of committing crimes, except those belonging to the following classes:
1.  Persons who committed the act or made the omission charged, under an ignorance or mistake of fact which disproves any criminal intent.
2.  Persons who committed the act charged without being conscious thereof.
3.  Persons who committed the act or made the omission charged, through misfortune or by accident, when it appears that there was not evil design, intention or culpable negligence.
4.  Persons (unless the crime be punishable with death) who committed the act or made the omission charged, under threats or menaces sufficient to show that they had reasonable cause to and did believe their lives would be endangered if they refused.