We would like you to assess the QUALITY of each of the following argument (discussing Death Penalty) and determine if the argument is Valid or Invalid. A valid argument is clearly interpretable and either expresses an argument, or a premise or a conclusion that can be used in an argument for the topic of death penalty. An invalid argument is a phrase that cannot be interpreted as an argument or not on the topic of death penalty.
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Question: I feel better putting them down, however, because an execution is a fitting response to the crime of murder.

Answer: Valid


Question: What gets little notice, however, is a series of academic studies over the last half-dozen years that claim to settle a once hotly debated argument ��� whether the death penalty acts as a deterrent to murder.

Answer: Valid


Question: Anti-gunners often mistakenly describe Castle Doctrine as "a licence to kill".

Answer:
Invalid