In my vew, there is no difference with murder or manslaughter. I lost my son last year through an act of mindless violence, by 5 men. only 1 of them were taken to court and the charges were dropped from murder to manslaughter, they said he was not killed intentionaly, so the most the killer would receive would be a 3 year prison sentence. He walked out of court after 3 days through lack of evidence. So wether they intended to kill him or not , my son would still be alive today.
If the sentences were the same for taking a life, then maybe it would learn people to keep their hands to themselves and the violent crime rate would be reduced.