Probably not, unless there was some intentionally negligent act associated with the situation.
If it could be proved that the person intentionally presented a loaded gun, then maybe. The exception to this might be if the person is legally carrying a loaded gun and is attempting to comply with a "no loaded guns" policy. In this case, the officer KNOWS the gun is loaded, though if he follows the safety rules, it won't matter.
Another exception might arise if the trigger mechanism has been modified in such a way that the gun has been made inherently unsafe and the owner knew this. Liability would be shared with the incompetent cop. A friend of mine let me fire his .22 target pistol. It felt like you could fire it by just breathing on the trigger. It was not a gun I ever wished to own.
There are two different scenarios that I have run across which present difficulties.
The first is when a round fails to discharge. You have to wait so that the primer becomes stable despite having possibly been struck by the firing pin. If the primer has been deformed by the attempt to fire it, then I could see how handling the gun with the defective round in the chamber could be risky.
Another situation I dislike intensely is using a revolver in single action mode. How does one safely lower the hammer on a live round? Everything about trying to lower the hammer slowly feels awkward and unsafe.
By first aiming carefully at the target, then squeezing the trigger. Moral of the story? Don't cock it unless you're ready to shoot it.