Final answer:
The exceptions to requiring a grand jury indictment for Class 3 and 4 misdemeanors include the non-application to states that may use preliminary hearings, and the exemption for armed forces from such proceedings.
Step-by-step explanation:
When discussing the exceptions to issuing a summons for Class 3 and Class 4 misdemeanors, it's important to understand the context provided by the Fifth Amendment. The first clause of this amendment suggests that serious crimes, typically felonies, require an indictment by a grand jury.
However, for less serious crimes, including Class 3 and 4 misdemeanors, this grand jury proceeding is not required. One of the exceptions is that this requirement does not apply to the states as the Fifth Amendment has not been incorporated at that level. Instead, states may require a preliminary hearing conducted by a judge to determine if there's sufficient evidence for a full trial. Additionally, those serving in the armed forces who are accused of crimes are exempt from grand jury proceedings as well.