No matter what topic they are writing about, historians agree on a set of general conventions:
Historians value counterargument. To draw a conclusion about why or how something happened, historians must weigh conflicting theories and interpretations carefully and judiciously. In an essay answering the question of why Congress passed the Nineteenth Amendment, you might conclude that politicians truly believed that women should have the right to vote. But you would also need to account for the failure of the same legislation several years earlier. Did politicians change their minds? Or were other factors at work?
Historians conduct research. Historians, like detectives or forensic specialists, look for explanations by assessing the available evidence rather than relying on assumptions or personal opinions. They look for multiple sources of evidence to confirm their theories, and they avoid value judgments.
Historians write in the past tense. Although historians consider their work relevant to the understanding of current events, they focus on past events, ideas, and movements and indicate this focus by using the past tense.
Historians credit the scholarship of others. Historians are aware that they are joining an existing scholarly conversation, and they place great importance on citing the ideas of other scholars.
Countering opposing arguments
Related topics:
Addressing skeptical audiences
Anticipating objections and countering opposing arguments
Building common ground
Past tense for writing about history