The 1968 Democratic National Convention in Chicago was marked by violent protests and clashes between police and demonstrators, leading to widespread criticism and controversy.

The Plank of Peace was a controversial plank in the 1968 Democratic Party platform that called for an immediate end to the Vietnam War. It was opposed by some party leaders, including President Lyndon B. Johnson.

The 2016 Democratic National Convention was marked by allegations of voter fraud and irregularities in the nomination process, leading to protests and calls for a recount.

The Superdelegate Rule at the 2016 Democratic National Convention gave superdelegates the power to overturn the results of the primary elections, leading to criticism and controversy.

The 1972 Democratic National Convention was marked by a floor fight over the nomination of George McGovern as the Democratic candidate for president, leading to a split in the party.

The Plank of Peace was a controversial plank in the 1972 Democratic Party platform that called for the legalization of marijuana. It was opposed by some party leaders, including Senator George McGovern.

The 1992 Democratic National Convention was marked by a floor fight over the nomination of Bill Clinton as the Democratic candidate for president, leading to a split in the party.

The Plank of Peace was a controversial plank in the 1992 Democratic Party platform that called for an end to the ban on gays and lesbians serving in the military. It was opposed by some party leaders, including Senator Al Gore.

The 2000 Democratic National Convention was marked by a floor fight over the nomination of Al Gore as the Democratic candidate for president, leading to a split in the party.

The Plank of Peace was a controversial plank in the 2000 Democratic Party platform that called for a ban on assault weapons. It was opposed by some party leaders, including Senator Joe Lieberman.

The 2008 Democratic National Convention was marked by a floor fight over the nomination of Barack Obama as the Democratic candidate for president, leading to a split in the party.

The Plank of Peace was a controversial plank in the 2008 Democratic Party platform that called for a single-payer healthcare system. It was opposed by some party leaders, including Senator Hillary Clinton.

The 2012 Republican National Convention was marked by a floor fight over the nomination of Mitt Romney as the Republican candidate for president, leading to a split in the party.

The Plank of Peace was a controversial plank in the 2012 Republican Party platform that called for a ban on same-sex marriage. It was opposed by some party leaders, including Governor Chris Christie.

The 2016 Republican National Convention was marked by a floor fight over the nomination of Donald Trump as the Republican candidate for president, leading to a split in the party.