  A distant, massive planet in the outer solar system has recently been
proposed to explain some observed features of extreme trans-Neptunian objects
(TNOs). Here we use N-body simulations of the formation of the Kuiper belt and
Oort cloud as well as a survey simulator to compare models of the solar system
with and without a 9th planet to one another as well as to observations. The
main mechanism for TNOs to be deposited into the distant ($a$ > au), detached
($q$ > au) region of the Kuiper Belt in the 8-planet model is Kozai-Lidov
oscillation of objects in mean motion resonances (MMR) with Neptune. This
effect does not deposit low-inclination ($i \lesssim$ 20{\deg}) objects into
this region. However, we find that the 9th planet generates a group of distant,
detached TNOs at low inclinations that are not present in the 8-planet model.
This disparity between the 8-planet and the 9-planet models could provide a
strong constraint on a possible planet 9 with further detections of TNOs in the
distant, detached region of the Kuiper Belt.
