Complex sentence: Generally, parliamentary groups have some independence from the wider party organisations, since it is felt that it would be improper for elected MPs to take instructions from non-elected party officials or from the small subset of the electorate represented by party members.
Split into simpler sentences: Generally, parliamentary groups have some independence from the wider party organisations. It is often thought improper for elected MPs to take instructions solely from non-elected party officials or from the small subset of the electorate represented by party members.