I think he staged it to look like suicide, but cannot rule out completely that maybe he was trying to make it look like murder. The position of the hands doesn't jive with making it look like a suicide to me. However, if he was trying to make it look like murder, surely he wouldn't have left the gun there. No reason to at all. Also, he would be opening himself up to much more intense questioning (whereabouts etc) than the softball questions he was asked.