sentences:  Many committees oversee existing programs in the context of hearings on related legislation, or routinely perform oversight when it is time to reauthorize a program, so oversight hearings may be combined with legislative hearings.Investigative hearings share some of the characteristics of legislative and oversight hearings.The difference lies in Congress's stated determination to investigate, usually when there is a suspicion of wrongdoing on the part of public officials acting in their official capacity, or private citizens whose activities suggest the need for a legislative remedy.