We model the odd-proton nucleus ${}^{223}\mathrm{Ac}$ as a ${}^{208}{\mathrm{P}\mathrm{b}+}^{14}\mathrm{C}+p$ system. The odd proton occupies ${0h}_{9/2},$ ${1f}_{7/2},$ and ${0i}_{13/2}$ states with energies taken from the known spectrum of ${}^{209}\mathrm{Bi},$ while the ${}^{14}\mathrm{C}$ cluster occupies ${0}^{+},$ ${2}^{+},$ ${4}^{+},\dots{},$ and ${1}^{\ensuremath{-}},$ ${3}^{\ensuremath{-}},$ ${5}^{\ensuremath{-}},\dots{},$ states, relative to ${}^{208}\mathrm{Pb},$ whose energies are taken from the known levels of ${}^{222}\mathrm{Ra}.$ The ${}^{14}\mathrm{C}\ensuremath{-}p$ interaction mixes together the various combinations of proton and ${}^{14}\mathrm{C}$ orbital motion states coupled to total angular momentum I. The Pauli principle is satisfied by excluding the odd proton from orbitals above the ${}^{208}\mathrm{Pb}$ Fermi surface already occupied by protons in the ${}^{14}\mathrm{C}$ cluster. We predict low-lying parity doublet bands with ${K}^{\ensuremath{\pi}}$ values ${\frac{5}{2}}^{\ifmmode\pm\else\textpm\fi{}}$ and ${\frac{3}{2}}^{\ifmmode\pm\else\textpm\fi{}},$ in agreement with observation.