The presidential election in the year 2000 between Vice President Al Gore and Governor of Texas, George W. Bush was a very tight race.
Near the end of the election, it was clear that whoever had the most votes in Florida would have enough to win the election and become the next president. Only a few hundred votes separated the two candidates, and many of the ballots were not marked properly or damaged. Gore demanded a recount of votes because it was too close.
The US Supreme Court sided with Bush and decided that a manual recount would violate the fourteenth amendment.
The connected amendment in this case is the fourteenth amendment. Bush argued that Florida was not treating its citizens fairly because different counties had different standards to decide which votes would count.
The Bush vs. Gore Supreme Court case impacted the fairness of future American elections and now when there is a close election, there are rules in place to keep everything structured and equal.