Early Wednesday morning, Missouri set a record for its number of executions in a year.

Paul Goodwin was the 10th man executed, more than any other year since the death penalty was reinstated in the state.

Goodwin was put to death for sexually assaulting Joan Crotts, a 63-year-old widow, and then killing her with a hammer in 1998 in St. Louis County.

In denying clemency, Gov. Jay Nixon referred to the crime as "brutal" and "senseless."

Crotts’ daughter told the Post-Dispatch that she planned on attending the execution. “I need to make sure in my own mind that that man is dead,” she said.

Goodwin’s attorneys had argued that their client wasn't fit to be executed due to his mental deficits, legally referred to as mental retardation or an intellectual disability.

The most recent assessment by a psychologist found Goodwin was “borderline-intellectually disabled” with an IQ of 73. Another assessment found Goodwin had the mental understanding of a 13 year old.

“The one absolute certainty for this examiner over the 12 years I have been involved with this case is that Paul Terrence Goodwin is now, and probably always has been, mentally retarded,” Denis Keyes wrote in concluding his examination.

“As such, if the state of Missouri proceeds with his judicial execution, then it is the devout opinion of this expert of 40 years experience in mental retardation, the state is doing so against the findings of both state and federal law, the Supreme Court and the Constitution of the United States of America,” Keyes wrote.

Attorney General Chris Koster's office pointed to an expert that testified at Goodwin's trial that said although his IQ was quite low, it did not mean he was mentally retarded.

The U.S. Supreme Court has ruled that executing those with severe mental deficits violates the constitution, as well as human dignity, and serves no legitimate purpose.

But the problem has been defining where the line should be. States set their own bar – and just last year, the U.S. Supreme Court ruled that a hard cutoff of a 70 IQ was not constitutional. The Supreme Court ruled that states should consider more than just an IQ when making the decision on whether a person is fit to be executed.

Missouri's drug protocol

Goodwin’s lawyers also asked the courts to halt the execution over concerns with the drugs the state uses. Missouri’s execution drugs have been the focus of controversy over the past year.

In October 2013, Gov. Jay Nixon announced that Missouri would buy the pentobarbital in its one-drug protocol from a compounding pharmacy, meaning its drugs would be mixed up on a per-order basis by a type of supplier that isn’t regulated by the Food and Drug Administration. The state said the pharmacy would be secret, going so far as to pay the pharmacy thousands in cash deliveries by a high-ranking state official.

But a few months later, St. Louis Public Radio revealed Missouri’s execution drug supplier was an out-of-state pharmacy that wasn’t licensed to sell in Missouri and had been cited for questionable practices. A death row inmate sued the pharmacy but settled out of court after the drug supplier agreed not to sell to Missouri anymore.

Missouri then found another supplier, and it has withheld all documentation on its qualifications, including if it is legally allowed to sell in the state.

Several months later, another St. Louis Public Radio investigation found Missouri had been injecting more drugs into the inmates than it had originally let on. The execution team was using midazolam, a drug that Corrections officials swore that they would not use, and injecting it before press witnesses were present.

The state then said the drug would be optional for the inmates. According to chemical log forms we obtained, the state has not used the drug since its use was revealed.

"Making the drug optional appears to be an acknowledgment that mandated injection of dangerous levels of midazolam shortly before the execution likely violates the inmate's constitutional rights," wrote several federal judges in a dissent on whether Missouri should be allowed to continue its executions.

So far, the courts have permitted Missouri’s execution pace to proceed, arguing that the inmates’ concerns over the procedures are irrelevant unless they name a better way for their executions to be carried out.

Four Supreme Court Justices (Elena Kagan, Ruth Bader Ginsburg, Stephen Breyer, and Sonia Sotomayor) indicated that they would grant a stay due to a case against Missouri for its drug practices.

Follow Chris McDaniel on Twitter: @csmcdaniel