What do you think are Paylor's motives in allowing Katniss to come face to face with Snow?

Commander Paylor's early life is unknown, however, as a resident of District 8, she most likely worked in the district's textile factories like most other citizens.  

Katniss first meets Paylor when she goes to District 8's hospital in order to film a propo for the Airtime Assault on the Capitol. Paylor takes Katniss along with Gale Hawthorne, Boggs, and the TV crew into the hospital. Paylor watches Katniss closely, to see what she is made of and if they have been right to count on her.

Paylor in District 8.

After Katniss leaves the hospital, hovercrafts from the Capitol fly in and begin to bomb the hospital. In an effort to fight against the bombers, Katniss and Gale climb to the roof of a warehouse that has machine gun nests. This is where they run into Commander Paylor again. Together, they all work to destroy the other waves of hovercrafts that fly overhead.

Commander Paylor later returns in the story when Katniss is living in President Snow's mansion, awaiting his execution. Katniss follows the strong scent of Snow's roses until she finds a room that is being guarded by two soldiers who at first do not permit her entrance to the room because they are following President Coin's orders. However, when Paylor appears, she instructs the soldiers to let Katniss go in and they obey her authority. Katniss enters to find President Snow and the two of them have a brief conversation. Snow informs Katniss that it was not him who bombed the children and ultimately killed Prim, but that instead it was President Coin who was behind it. When Katniss emerges, Paylor asks her, "Did you find what you were looking for?", and Katniss holds up rose, which Paylor takes as an affirmative response. This seems to imply that Paylor was somehow aware of Coin's betrayal and wanted Katniss to find out.

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