Parliamentary Private Secretary to the Prime Minister
Margaret Thatcher's downfall from the Conservative Party leadership in 1990 is attributed by many to the actions of her Parliamentary Private Secretary , Peter Morrison , in failing accurately to count votes amongst Conservative backbenchers . 
<triplet> Margaret Thatcher <subj> Conservative <obj> member of political party <triplet> Conservative Party leadership in 1990 <subj> 1990 <obj> point in time <triplet> Peter Morrison <subj> Conservative <obj> member of political party