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Following the action on New Caprica, Nowart and fellow Marine Henry Cheadle are assigned to provide security to Dogsville, where they are witness to the confrontation between Karl Agathon and Michael Robert. Following that incident, Nowart is reassigned, once more with Cheadle, to protect Gaius Baltar's lawyer, Romo Lampkin. Though Cheadle is killed by a bomb made by Aaron Kelly, Nowart manages to successfully protect Lampkin until the trial.
When Kara Thrace unexpectedly returns from the dead, Nowart, along with fellow NCO Sergeant Brandy Harder, is one of the Marines assigned to escort her through Galactica. Both are incapacitated when Thrace takes Laura Roslin hostage.
Nowart does take part in Felix Gaeta's mutiny, but is less than fully committed to it, and permits Admiral Adama and Colonel Saul Tigh to escape his custody. Adama and Tigh take him hostage, but later permit him to escape, although he narrowly avoids being shot in the back by Kara Thrace (The Oath).
Nowart survived the events of the mutiny, and when Admiral Adama called for people to volunteer to rescue Hera Agathon, he was one of those to do so.
As part of Lee Adama's Alpha Team, Nowart boarded the Colony (he is the Marine who informs Lee that the Colony interior is pressurized), and rescued young Agathon. Despite heavy resistance, he managed to return to Galactica alive. It is unknown whether or not he survived the subsequent boarding by the Cylons. If he did, he presumably settled on New Earth with the rest of humanity's remnants (Daybreak, Part II).