Liam Binet is a synth sympathizer who uses his position in The Institute to free synths. Without certainty of the Railroad's existence, he sends freed synths to the surface in hopes that somebody will rescue them. However when encountering a Railroad-affiliated Sole Survivor, he will express his support and admiration, overwhelmed at the knowledge that there are others fighting to free synths.
Despite this, he is opposed to any kind of violence - including the destruction of The Institute. After the Sole Survivor destroys The Institute in The Nuclear Option, he leaves a suicide note behind for the player, expressing animosity and hatred for the Sole Survivor, and explaining that everyone he knows, including his father, has been killed due to the player's actions. His body is retrieved by The Railroad and buried in the Old North Church.
If engaged in conversation after siding with the Institute, he will enquire about the progress of the plan to free the thirteen synths, to which the Sole Survivor can say they aren't going forward with it.