This proposal investigates the misleading potential of graphs with dual vertical axes: one on the left and one on the right. While graphs help convey complex data, they can also cause misinterpretations. This study fills a gap in literature and design advice by examining if and how dual-axis graphs mislead, and how alternatives compare. Quantitative and qualitative research will test currently unsupported claims about how readers (mis)interpret such graphs and explore interpretation strategies. The findings will offer insights into best practices for data communication, helping journalists, editors, and analysts present information accessibly and accurately.