  The largest trans-Neptunian objects (TNOs) represent an extremely diverse
collection of primitive bodies in the outer solar system. The community
typically refers to these objects as dwarf planets, though the IAU acknowledges
only four TNOs officially as such: Pluto, Eris, Makemake, and Haumea. We
present a list of 36 potential candidates for reclassification as dwarf
planets, namely candidate dwarf planets (CDPs), which cover a wide range of
sizes, geometric albedos, surface colors and probably, composition.
Understanding the properties across this population, and how those properties
change with size, will yield useful constraints on the environment in which
these TNOs formed, as well as their dynamical evolution, and bulk interior
composition. TNO surface characteristics are ideal for study with the James
Webb Space Telescope (JWST), which provides imaging and spectroscopic
capabilities from 0.6 to 28 $\mu$m. The four available science instruments,
MIRI, NIRCam, NIRISS, and NIRSpec, and their capabilities for the study of
TNOs, are presented. JWST will expand on the wavelength range observable from
the ground in the near-infrared (0.6-5 $\mu$m) for compositional studies and
will open a new window on TNOs in the mid-infrared (5-28 $\mu$m) for thermal
characterization.
