Complex sentence: As Home Secretary, he was responsible for the British Government's Northern Irish policy during the period that included Bloody Sunday in 1972; shortly thereafter, he left office due to an unrelated scandal in one of the companies of which he was director.
Split into simpler sentences: As Home Secretary, he was responsible for the British Government's Northern Ireland policy during the period that included Bloody Sunday in 1972. Shortly thereafter, he left office due to an unrelated scandal in one of the companies of which he was director.