a. Necessity. Conduct which would otherwise be an offense is justifiable by reason of necessity to the extent permitted by law and as to which neither the code nor other statutory law defining the offense provides exceptions or defenses dealing with the specific situation involved and a legislative purpose to exclude the justification claimed does not otherwise plainly appear.
b. Other justifications in general. Conduct which would otherwise be an offense is justifiable by reason of any defense of justification provided by law for which neither the code nor other statutory law defining the offense provides exceptions or defenses dealing with the specific situation involved and a legislative purpose to exclude the justification claimed does not otherwise plainly appear.