Why was the election of 1800s decided in the house of repersentitives?

The election of 1800 was decided in the House of Representatives because none of the candidates, namely Thomas Jefferson and Aaron Burr, received a majority of the electoral votes that were cast.

To understand why this happened, we need to go back to the Founding Fathers' original system of electing the President and Vice President, as outlined in the United States Constitution. Under this system, each state is allocated a certain number of electoral votes based on its representation in Congress, including both Senators and Representatives. In the 1800 election, there were a total of 138 electoral votes up for grabs.

Thomas Jefferson and Aaron Burr were both Democratic-Republican candidates, running against the Federalist incumbent, John Adams. The electors who supported Jefferson and Burr had intended for one of them to be elected President, while the other would become the Vice President. However, due to a flaw in the electoral process at the time, both candidates received an equal number of electoral votes – 73 votes each.

According to the Constitution, if no candidate receives a majority of the electoral votes (which at that time was half plus one, or 70 votes), the election would then be decided by the House of Representatives. Each state delegation in the House would have a single vote, meaning that even the most populous states would have the same amount of influence as the smallest. This was a deliberate check and balance designed to prevent the more populous states from overwhelming the rest.

At this point, the Federalists, who held a majority of state delegations in the House, had the power to decide the outcome. After several rounds of voting, they ultimately threw their support behind Thomas Jefferson, who was seen as the lesser of two evils compared to Burr. Finally, on the 36th ballot, Jefferson secured the majority of the state delegations' votes and was elected President.

In response to this election, the 12th Amendment to the Constitution was ratified in 1804, which changed the electoral process and ensured that separate votes would be cast for President and Vice President, avoiding the confusion and deadlock that occurred in the election of 1800.