I'd say this, from the thread the comrade linked here. Also, there is not a "Marxist-Leninist take" on everything, it's not the scope of Marxism-Leninism to "have an opinion" on everything, Marxism-Leninism is a theoretical framework which guides revolutionary praxis

My personal take on this is that death penalties should have a democratic process behind it, it's the safest path. No one is irredeemable, but some deaths are warranted, for symbolic, political, social reasons. Once the facts have been established and their crimes fully investigated, the death of a serial killer may bring comfort to several families affected, for instance. Or the leader of a genocidal fascist movement may be politically and/or symbolically warranted