I want to ask a question,can you tell me is death penalty cheaper than other punishiments?sorry,it is punishment

in many countries, death penalty is more cheaper than other punishment. in california, the death penalty should spend 1.3 million dollar per year, but the life in * should spend 11.5 million per year. it is more cheaper than other punishment.
And in Maryland, (“Death penalty costs Md. less than life term,” by Jennifer McMenamin, The Baltimore Sun, March 6, 2008).

不太明白，为什么问死刑是不是比其他处罚要低呢？而且，不是PUNISHINMENTS ,而是PUNISHMENT,不能有S跟I

我想问一个问题,你能告诉我,死刑（death penalty)比其他刑罚更省事(cheap)吗?

i think death is very sample, just handle the problem in seconds