Austin, Jan 30 (IANS/EFE): The US state of Texas executed convicted killer Robert Ladd who was jailed for the murder of a woman in 1996 after the Supreme Court rejected the defence's last minute argument of intellectual disability.
Ladd, a 57-year-old African-American, was declared dead Thursday after receiving a lethal injection at Huntsville prison, according to the Texas Department of Criminal Justice.
Witnesses to the execution were two people who Ladd had exchanged correspondence with during his imprisonment.
Minutes before the execution was carried out, the US Supreme Court turned down an appeal by Ladd's lawyers who argued that the execution contradicts a ruling by the court in 2002 that prohibited the death penalty for people with intellectual disabilities.
The lawyers argued that in 1970, under the tutelage of the Texas Youth Commission, a psychiatrist found the IQ of the convicted person in that case to be below standards.
They also claimed that as an adult Ladd received treatment at Andrews Center, an institution that treats people with intellectual disabilities.
Despite these arguments, the Supreme Court took this decision unanimously.
On Tuesday, the Supreme Court also rejected a similar defence by the lawyers of the allegedly intellectually disabled Warren Hill who was executed in Georgia.
Ladd was sentenced to death for the murder of Vicki Ann Garner, a 38-year-old woman whom he abused sexually, then strangled, hit her with a hammer and finally burned her body at her residence in Tyler, Texas.
Sixteen years earlier, in 1980, Ladd had committed a nearly identical crime: he stabbed a woman in her apartment in Dallas and set the body on fire, triggering a big blaze that also killed the victim's two daughters.
He was placed on probation in 1992 after serving 12 years in prison for those murders.
Ladd became the second prisoner executed in 2015 in Texas.
Since the death penalty was reinstated in 1976, Texas has executed 519 prisoners accounting for 40 percent of the 1,400 executed nationwide.