Liberal across the decade have been criticised for their hectoring tone.
Now a scientific study has confirmed left-wing politicians really do have a tendency to lecture people on their beliefs.
Researchers who analysed more than 380,000 speeches, including those given by Nick Clegg and Gordon Brown, have concluded that ‘liberals lecture’ while, in comparison, ‘conservatives communicate’.
The analysis is based on the complexity of the language used by the politicians, including long-winded sentences and difficult words.
Conservatives, whose lives have been claimed to be ‘more orderly, conventional and neat’, use simpler language.
Liberals, who may have a higher tolerance for ambiguity, use complex language or ‘lecture’.
Dr Martijn Schoonvelde, of University College Dublin, said: ‘Conservatives speak in more simple language which, by and large, is more easily understood by the public.
‘Liberals use longer words and longer sentences, maybe because they speak like that or perhaps because that is what the people they are addressing want.