Death Penalty- Is it Right?

I do believe that in most cases death penalty is a deterrent to crime because if a person kills a whole bunch of people(on purpose) then they deserve to die because they will probably just end up doing it again. So for the public safety, serial killers and really horrible murderers can get the death penalty. When serial killers are killed they will never be out in public again, killing innocent people.
The biggest weakness is that if someone does receive capital punishment but they are innocent, the an innocent person just died for no reason! It's not fair if an innocent person dies in place of someone who is guilty and out in public still.
However, the biggest benefit of death penalty is that it would take serial killers and murders off of our streets forever. This is a big benefit because it makes the public feel safe and it is a great deterrent as well.
I cannot beleive that it costs so much money to keep a prisoner in jail for one year, and how much the death penalty is. It is a lot of money. I think that they should use death penalty when they really need to, and to incarcerate super serious crimes. And if possinble to use rehab more often because its less money and it is beneficial to the offender!

Insanity

I believe that the insane law can be a good law at times. I think that it is necessary to have this law because if someone really is insane then they have to plea it (like the Yates case). But a lot of people take advantage of the insanity plea because they want a lesser punishment. I think that doing that is messed up becasue you can't fake at being insane, so its just a waste of time faking it.
I believe that insanity should be considered in criminal cases because some people really are insane and don't know right from wrong. If you severely punish an insane person they will not understand why they are getting punished so harshly. So i think that a good punishment for an insane person is for them to be placed into a mental facility where they will be locked up and would not be able to leave the campus/mental facility.
I believe that a person is insane when they don't know the difference between roght and wrong. Like Andrea Yates, she was insane because she killed her 5 young kids because satan told her to. She thought that she was being a bad mother and that by killing her kids she was actually saving them. I think that Yates should be in a closed mental facility, not an open campus because she can potentially be a harm to society because if she killed her own kids, what would stop her from killing complete strangers. She loved her kids so killing them would be a lot harder and more emotionally painful then killing complete strangers. She deserves to be in a mental facility/psychiatric ward forever.