Mexican who gunned down Houston cop WILL be executed tonight despite last-minute pleas from Mexico government

Edgar Tamayo is scheduled for lethal injection at a Texas prison

Death-row inmate, 46, was convicted of murdering Guy Gaddis in 1994



Lawyers argues Tamayo was mentally impaired so ineligible for execution

Court ruled that appeal was filed too late to prevent execution today

High-profile case is a focus of protests in Mexico and diplomatic pressure

Mexican government said it 'strongly opposed' the execution



No clemency: Edgar Tamayo will be executed for murdering Houston police officer Guy Gaddis in 1994

A Mexican held on death-row in a Texan prison for murdering a policeman will be executed tonight despite last-ditch appeals from lawyers for clemency.

Edgar Arias Tamayo, 46, was set for lethal injection this evening for shooting of Guy Gaddis, 24, in January 1994.

The case has been a focus of protests in his home town and diplomatic pressure, with U.S. Secretary of State John Kerry calling for a delay to Tamayo's execution.

Tamayo's lawyers had lodged an appeal arguing that he was ineligible for the death penalty due to mental impairment.

But a court ruled the appeal had been filed too late.



Gaddis, who had been on the force for two years, was driving Tamayo and another man from a robbery scene when evidence showed the officer was shot three times in the head and neck with a pistol Tamayo had concealed in his pants.



The car crashed, and Tamayo fled on foot but was captured a few blocks away, still in handcuffs, carrying the robbery victim's watch and wearing the victim's necklace.

Tamayo's attorneys and the Mexican government contend Tamayo's case was tainted because he wasn't advised under an international agreement that he could get legal help from his home nation following his arrest.

Secretary of State John Kerry previously asked Texas Attorney General Greg Abbott to delay Tamayo's punishment, saying it 'could impact the way American citizens are treated in other countries.' The State Department repeated that stance Tuesday.

But Abbott's office and the Harris County district attorney opposed postponing what would be the first execution this year in the nation's most active capital punishment state, where 16 people were put to death in 2013. At least two other inmates in similar circumstances were executed in Texas in recent years.

The Mexican government said in a statement this week it 'strongly opposed' the execution and said failure to review Tamayo's case and reconsider his sentence would be 'a clear violation by the United States of its international obligations.'



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Pleas for mercy: A woman holds up a sign showing a photo of Texas death-row inmate Edgar Tamayo that reads in Spanish 'The town of Miacatlan offers you our support, during a protest demanding clemency

Mexican officials and Tamayo's attorneys contend he was protected under a provision of the 1963 Vienna Convention on Consular Relations.



Legal assistance guaranteed under that treaty could have uncovered evidence to contest the capital murder charge or provide evidence to keep Tamayo off death row, they said.

Rejected: A request by U.S. Secretary of State John Kerry, pictured, to delay Tamayo's punishment was rejected

'We are continuing to pursue our options for appeal, and vindication of Mr Tamayo's right to review of the consular rights violation in his case,' said Maurie Levin, one of Tamayo's lawyers.

Tamayo's attorneys previously appealed to a federal court in Austin for an injunction against Gov. Rick Perry and the Texas Board of Pardons and Paroles, which he appoints.



The board can recommend Perry grant clemency, but it's an action they rarely take. A judge rejected that lawsuit Tuesday.

'It doesn't matter where you're from,' Perry spokeswoman Lucy Nashed said.



'If you commit a despicable crime like this in Texas, you are subject to our state laws, including a fair trial by jury and the ultimate penalty.'

Tamayo was in the U.S. illegally and had a criminal record in California, where he had served time for robbery and was paroled, according to prison records.

'Not one person is claiming the suspect didn't kill Guy Gaddis,' Ray Hunt, president of the Houston Police Officers' Union, said. 'He had the same rights as you and I would have.

'This has been looked at, heard, examined and it's time for the verdict of the jury to be carried out.'

Tamayo was among more than four dozen Mexican nationals awaiting execution in the U.S. when the International Court of Justice in The Hague, Netherlands, ruled in 2004 they hadn't been advised properly of their consular rights.



The Supreme Court subsequently said hearings urged by the international court in those inmates' cases could be mandated only if Congress implemented legislation to do so.