I don't often post more than one answer, but this idea might be worth it, and it is too different from my first answer.

You get a discount on the funeral if the body is sold as a zombie worker.

These zombie workers become an alternate revenue source for funeral homes. Whether burying or cremating, we need to dispose of dead bodies. Even today, burial or cremation costs money. If the bodies are zombified, then you don't need to pay for the disposal. Better yet, the funeral home would sell the bodies for a reduced funeral rate.

This deincentifies murder, because only funeral homes are allowed by law to do this. In order to sell a zombie worker, you need to lose a loved one and pay (a reduced rate) for a funeral.

Nobody but the funeral home has a positive financial incentive. Living relatives still pay money, just not as much. No sense in killing that annoying uncle, because it will still cost you money. It's cheaper to just not invite him to family gatherings.

Prison's won't make money either, because the family still pays for the funeral. The prison gets nothing (but an empty cell).

Criminal gangs won't go around killing people, because murder is still illegal, and they would need to be a registered funeral practitioner before they can sell bodies.

Documentation signed by living relatives at the funeral home would need to be sent to the government. Employers would need permits to use the undead, which could be tied back to the funeral home paperwork and death certificates. The government would need to audit employers periodically, of course. Punish those who do not abide by the law severely.

Nothing kills the incentive to murder like boring paperwork and discounts on things nobody really wants to buy. And nobody really wants to buy funeral ceremonies.

I don't often post more than one answer, but this idea might be worth it, and it is too different from my first answer.

You get a discount on the funeral if the body is sold as a zombie worker.

These zombie workers become an alternate revenue source for funeral homes. Whether burying or cremating, we need to dispose of dead bodies. Even today, burial or cremation costs money. If the bodies are zombified, then you don't need to pay for the disposal. Better yet, the funeral home would sell the bodies for a reduced funeral rate.

This disincentivizes murder, because only funeral homes are allowed by law to do this. In order to sell a zombie worker, you need to lose a loved one and pay (a reduced rate) for a funeral.

Nobody but the funeral home has a positive financial incentive. Living relatives still pay money, just not as much. No sense in killing that annoying uncle, because it will still cost you money. It's cheaper to just not invite him to family gatherings.

Prison's won't make money either, because the family still pays for the funeral. The prison gets nothing (but an empty cell).

Criminal gangs won't go around killing people, because murder is still illegal, and they would need to be a registered funeral practitioner before they can sell bodies.

Documentation signed by living relatives at the funeral home would need to be sent to the government. Employers would need permits to use the undead, which could be tied back to the funeral home paperwork and death certificates. The government would need to audit employers periodically, of course. Punish those who do not abide by the law severely.

Nothing kills the incentive to murder like boring paperwork and discounts on things nobody really wants to buy. And nobody really wants to buy funeral ceremonies.