1. A method, in a data processing system, for managing virtual discussion threads in a synchronous conferencing system the method comprising: storing sent and received chat entries in a chat session data structure wherein the chat session data structure stores a history of chat entries of a chat session; receiving user selection of a plurality of chat entries belonging to a virtual discussion thread in a chat session graphical user interface of the chat session; marking the plurality of chat entries as belonging to the virtual discussion thread in the chat session data structure, wherein each chat entry within plurality of chat entries in the chat session data structure comprises a message identifier, a user identifier, a timestamp, a chat message text, and a virtual discussion thread identifier; adding a message identifier for each of the plurality of chat entries to a virtual discussion entry in a virtual discussion data structure, wherein the virtual discussion entry in the virtual discussion data structure comprises a virtual discussion thread identifier, a message identifier list, and an evidence mode field; and activating an evidence mode corresponding to the evidence mode field for the plurality of chat entries in the chat session graphical user interface; wherein receiving user selection of the plurality of chat entries comprises: receiving user selection of a portion of a chat message associated with a given chat entry within the plurality of chat entries; and identifying coordinates of the selected portion of the chat message, wherein the coordinates comprise a start position and end position that identify the first and last characters of the selected portion of the chat message that belongs to the virtual discussion thread, wherein marking the plurality of chat entries as belonging to the virtual discussion thread comprises storing the coordinates in association with the message identifier of the chat message in the given chat entry in the chat session data structure such that an unselected portion of the chat message is not marked as belonging to the virtual discussion thread.
9. The method of claim 1 , wherein activating the evidence mode for the plurality of chat entries comprises activating the evidence mode based on user preferences.