Pedophilia, whether we like it or not, is natural.
That doesn't justify it in society, but what message does this send out to pedophiles? follow your natural urges and you will be killed? So basically, pedophiles are going to keep their feelings secret rather than seek psychiatric help thus perhaps leading to more children being raped in the future.
Just thought I'd let you know that killing criminal's doesn't mean there will be less crime.