Why should we (not) be concerned about the Death Penalty in Texas?

(From:http://www.deathpenaltyinfo.org/sentencing-life-americans-embrace-alternatives-death-penalty)

There are many, many, arguments to be made about the Death Penalty. Is it humane? Is it constitutional? Is it fair? Most of these issues are argued along moral grounds,backed with little evidence and lots of personal bias. The issue I seek to explore is: Does the Death Penalty make sense? What I mean is does it make both fiscal, and ethical sense to continue to carry out the Death Penalty as a form of punishment for crimes in our legal system. The exigence is clear, several people are put to death every year, and millions of tax payer's dollars fund their deaths. If the Death Penalty and lethal injection are not logical, then both those being put to death and those paying for those deaths deserve to know in order to avoid death and save millions of dollars. Also, in order to justify the continued use of the Death Penalty, one supporting the other side must prove that it is indeed logical.
Also, another exigence of this argument is that people must be informed on the true consequences of the death penalty. Many people are misinformed and believe that lethal injection is a ridiculously expensive procedure, however most of the costs associated with the Death Penalty are derived from the trials which "cost 3 times more than non-death penalty cases, or $3 million for a single case", according to an Urban Institute Study quoted in Forbes. After having researched some I can also say that most of the numbers people use in their arguments against the death penalty tend to be rather irrelevant, since they are quoted mostly from a Dallas newspaper in 1992. Part of what I will attempt to do to respond to this exigence is find proper and accurate data to decide whether the Death Penalty is logical or not.
This issue has a very large rhetorical audience. Some may say that they don't care, but every year every single tax payer in Texas pays for the legal fees of Death Penalty cases as well as the costs of lethal injection, which according to the BBC "has risen 15-fold since 2010, when they cost the state $86." Even if one is not a tax payer of a death penalty state, they might be part of the argument on purely humanitarian grounds as well.
It's an issue that encompasses almost everyone in the United States, and it leads to very different opinions, but opinions matter much less when facts show an opinion is illogical.

http://www.forbes.com/sites/kellyphillipserb/2011/09/22/death-and-taxes-the-real-cost-of-the-death-penalty/
http://www.bbc.com/news/magazine-17210285