The option of pardoning a murderer is gvery abuse prone it should be removed
It is a privilege of every Muslim, given to him by none other than his CREATOR himself. If one wants to forgive someone in his right senses and free will.................. nobody should have any objection to it. And forgiving is preferred if we believe in the judgement day.
And in my opinion the pardoning part is valid for capital punishment only, state can still jail a murderer even if he has been pardoned by the relatives of one he has murdered.