On the topic of history...
"After the fall of the Roman Republic, the constitutional balance of power shifted from the Roman Senate to the Roman Emperor. Though retaining its legal position as under the Republic, in practice, however the actual authority of the Imperial Senate was negligible, as the Emperor held the true power in the state. As such, membership in the Senate became sought after by individuals seeking prestige and social standing, rather than actual authority."
[https://en.wikipedia.org/wiki/Roman_senate#Senate_of_the_Rom...]
Imagine for a moment, further expansion of executive autonomy and power. Then review recent elections with the definition of populism in mind. There are stark similarities.
"When Hitler was appointed in January 1933, Germany was a democracy. Germany had fair elections; nobody had their right to vote abused; there were numerous political parties you could vote for etc. To pass a law, the Reichstag had to agree to it after a bill went through the normal processes of discussion, arguments etc. Within the Reichstag of January 1933, over 50% of those who held seats were against the Nazi Party. Therefore it would have been very unlikely for Hitler to have got passed into law what he wanted. Many saw Hitler as a fall-guy politician who would have to shoulder to blame if things got worse under his leadership.
Hitler had promised a general election for March 1933. This would have been, in his mind, the perfect opportunity for him to show all politicians who opposed him where the true loyalties lay in the German people. In fact, 1932 had shown Hitler that there was a possibility that support for the Nazis had peaked as their showing in the November 1932 election had shown. Anything other than a huge endorsement of Hitler and the Nazi Party would have been a disaster and a gamble which it is possible that Hitler did not want to take.
One week before the election was due to take place, the Reichstag building burned down. Hitler immediately declared that it was the signal for a communist takeover of the nation. Hitler knew that if he was to convince President Hindenburg to give him emergency powers - as stated in the Weimar Constitution - he had to play on the old president's fear of communism. What better than to convince him that the communists were about to take over the nation by force?"
[http://www.historylearningsite.co.uk/Nazi_Germany_dictatorsh...]
Even in a well formed government, there are possible scenarios that play out with catastrophic results. As politics become more polarized and government exerts more authority, it is more likely that individual opportunists can raise to dominant positions and wreak havoc on policy and settle vendettas against political opponents.