CP violation in $K_L$→${\pi }^{+}$${\pi }^{\mathrm{-}}$γ

We study the process $K_L$→${\pi }^{+}$ ${\pi }^{\mathrm{-}}$γ, looking for new information on CP violation. We find that CP violation in this process is dominated by the inner-bremsstrahlung contribution which gives no information different from what is known in $K_L$→ππ. Any CP violation in the direct emission appears to be too small to be observed. We also find that the direct-emission term is dominated by long-distance contributions to the electromagnetic form factor, and can be reasonably understood within a pole model.