The cabinet member who does not attend the State of the Union address rotates from year to year. This member is chosen by the White House chief of staff and sworn to secrecy, according to ABC News.
The cabinet member chosen to be excluded from the annual festivities is known as the designated survivor, ABC News reported. In the case of a cataclysmic event during the State of the Union speech— nuclear war, for example — the designated survivor is charged with the responsibility of becoming the next president. The chosen cabinet member attends several briefings on the continuity of the government. There is no clear pattern established in picking the cabinet member, but those holding higher-ranking cabinet positions, such as secretaries of state, treasury and defense, have never been chosen for this duty.