Known simply as Sarge, from his years in the Starfleet Marine Corps, CP Muldoon is a gruff and taciturn man. Nothing is warm about his demeanor. He served as a drill instructor at Starfleet Academy prior to his posting to SB 114. His voice is gravely, and it compliments his thin, wiry body.

He strives to keep the peace while his suspicious nature is constantly aroused. He is constantly aware of what is going on through his many connections, both legal and questionable. He has been married and divorced twice, no children. He is prone to drinking alone.