Troy Davis died insisting that he was not responsible for the death of police officer Mark MacPhail in 1989.

“I am sorry for your loss ... I did not personally kill your son, father and brother. I am innocent,” he told the slain officer's son and brother minutes before he breathed his last.

And many in the U.S. believe that Davis was innocent and that the legal system failed to deliver justice to an innocent man. Some drew comparisons between the case of Davis and the alleged miscarriage of justice that set Casey Anthony free recently.

The social networking sites were abuzz with cries of protests and agitated criticisms against the justice system.

Many commentators could not refrain from making comparisons with the Casey Anthony case where the alleged child-killer was set free despite having a body of evidence against her.

Casey Anthony is offered a book deal, but Troy Davis is only offered his last meal. Wake up America, our justice system is screwed, wrote Ryan Hunt on Twitter.

shana wilson had this to add: Casey Anthony NOT Guilty, Troy Davis Being Executed ... Everybody Hates Chris But Everybody Loves Raymond ...
Another one: “With evidence, Casey Anthony is set free. Without it, Troy Davis gets the dealth penalty. Welcome to America wrote MrNiceCreps Chumes.

Davis was convicted in 1991 on the basis of witness accounts that said he was seen shooting police officer Mark MacPhail in Savannah in 1989. He was 19 years old when he was arrested for the murder. The 42-year-old had long professed he's innocent of killing the off-duty police officer.

However, according to Davis's defense team, his death sentence was wrong as the conviction was allegedly based on flawed testimony by witnesses. They also point out that some testimonies were largely recanted later.

Dear AMERICA, we don't know if Troy Davis killed a man...But we know you killed Troy Davis, POPGATES wrote on Twitter, highlighting the alleged uncertainty over Davis' guilt.

Dear Georgia, we dont know if Troy Davis killed a man. Neither do u. But we know u killed Troy Davis, wrote Austin Keller.
So I wake up to hear they executed Troy Davis. Wonder if most Americans realize how far out of step they are with international norms, wrote Hari Kunzru.

While you were sleeping Troy Davis was executed at 5:23am. His last words were I am innocent, wrote Ryan Cameron.

However, the family of the killed police officer says justice to him will be served when Davis is executed. Justice was finally served for my father ... The truth was finally heard, the dead officer's son said days before the execution, according to CBS News.

Some people saw the death of Davis as an opportunity to campaign for the end of capital punishment in the U.S. I genuinely cannot believe we live in a day/age where the death penalty exists in the USA. Shame on you today Georgia, wrote Loulou Androlia.