How a few adjustments can improve online political debates

Lisa Lock
scientific editor

Robert Egan
associate editor

Online political debates are often characterized by sharp divisions, personal attacks and a low level of information. But a new study from the University of Copenhagen and King's College London shows that this does not have to be the case. By adjusting just a few elements in the way we debate, the quality of the conversation can be significantly improved. However, a better tone of debate does not necessarily change people's attitudes, the researchers behind the study point out.
The , published in the journal Science Advances, was conducted by Tobias Heide-Jørgensen, Gregory Eady and Anne Rasmussen. Using large language models (LLMs) such as ChatGPT, they conducted experiments with more than 3,000 citizens in the United States and the United Kingdom.
"The study differs from previous research in that it uses large language models such as ChatGPT to generate counterarguments tailored to each participant. This makes it possible to test debate strategies in a more natural and personal way," explains Professor Rasmussen.
Debaters mirror each other
Participants were presented with counterarguments that varied in tone, type of argumentation, willingness to compromise and party political signaling. The results were clear.
"When counterarguments are respectful, based on facts and signal openness to compromise, the likelihood of the opponent responding with a high-quality contribution doubles," says Associate Professor Eady.
The study shows that proposals for compromise not only increase the willingness to compromise, but also reduce disrespect in responses. Evidence-based arguments have similar effects and contribute to a more civil and constructive conversation. These elements reinforce each other and create a more respectful and open debate.
"Participants perceive those who use respect, evidence and compromise as more open, informed and constructive. This explains why these approaches promote better conversations," says Eady.
Also works in toxic environments
The positive effects of a respectful tone and evidence hold true even in polarized and toxic debate environments—and when participants interact with political opponents.
"This shows that constructive debate strategies are robust, even under difficult conditions," says Rasmussen.
Although the tone and quality of the debate can be improved, this does not necessarily change people's political attitudes.
"We see no signs that people change their minds, even when they encounter high-quality arguments," explains Rasmussen. "But that doesn't mean it's a waste. Creating a more open and respectful debate culture is in itself a democratic gain."
AI can promote debate culture
The researchers hope that their findings can be used to improve debate formats on social media and in political discussions in general.
"Our study shows that it is actually possible to change the tone of the debate—and that doesn't necessarily require people to change their attitudes, just their approach," says Rasmussen.
"Our results can contribute to understanding how we can create more constructive political dialogue in an era characterized by polarization and misinformation. At the same time, we show that artificial intelligence can play a role in promoting a better culture of debate."
More information: Tobias Heide-Jørgensen et al, Understanding the success and failure of online political debate: Experimental evidence using large language models, Science Advances (2025).
Journal information: Science Advances
Provided by University of Copenhagen