Death row inmate who always maintained his innocence executed by lethal injection

A death row inmate who always maintained his innocence has been executed for the abduction, rape and murder of a student more than 20 years ago.

Larry Swearingen received a lethal injection at the state penitentiary in the Texan city of Huntsville for the 1998 killing of 19-year-old Melissa Trotter.

The teenager was last seen her leaving her community college in Conroe, a small city north of Houston that December. Her body was found in a forest around 70 miles away.

After he was convicted two years later, Swearingen always maintained his innocence in her death and claimed that his conviction was based on junk science.

The 48-year-old had previously received five stays of execution, but having exhausted all routes for appeal, he became the twelfth inmate to be put to death in the US this year and the fourth in Texas, where 11 more executions are scheduled this year.

Describing him as a sociopath with a criminal history of violence against women, prosecutors said they stood behind the "mountain of evidence" used to convict him in 2000.

They said he even tried to get a fellow death row inmate to take the blame for his crime.

Swearingen had long tried to cast doubt on the evidence used to convict him, particularly claims by prosecution experts that Trotter's body had been in the woods for 25 days.

His longtime attorney, James Rytting, said at least five defence experts concluded her body was there for no more than 14 days, and because Swearingen had been arrested by then on outstanding traffic violations, he could not have left her body there.

He said his client, who was also represented by the Innocence Project, was guilty of doing "some very stupid things," but prosecutors didn't have proof he killed Trotter.

Mr Rytting also maintained a piece of pantyhose used to strangle Trotter was not a match to a piece found in Swearingen's trailer. He also disputed prosecution experts' claims dismissing blood found in Trotter's fingernail shavings that was determined to not be Swearingen's.

The Texas Department of Public Safety had also said in letters that its technicians should not have been as definitive in their testimony about the blood found in the fingernails and the pantyhose match.

Swearingen was put to death after the US Supreme Court rejected his final appeal, which focused on allegations prosecutors used "false and misleading testimony" related to blood evidence and a piece of pantyhose used to strangle Trotter.

Kelly Blackburn, the trial bureau chief for the Montgomery County District Attorney's Office, which prosecuted Swearingen, said his efforts to discredit the evidence were unsuccessful because his experts' opinions didn't "hold water."

He said he had "absolutely zero doubt" that they had prosecuted the right man.

Mr Blackburn added Swearingen killed Trotter because he was angry that she had stood him up for a date. At the time of Trotter's killing, Swearingen had also been charged with kidnapping a former fiancee.

Swearingen also tried to get people to lie to give himself an alibi, Mr Blackburn said, adding that he got another inmate to write a letter in Spanish that professed to be from the real killer and had it sent to his attorney.

Anthony Shore, who he concocted the plan with, was executed last year.

Agencies contributed to this report