In the message, written prior to his conviction, Mehserle begins by saying, "I hope those who hate me and those who understand that I never intended to shoot Oscar Grant, will listen to this message."
Family supporters have blasted Mehserle for not apologizing sooner.
"In every other instance, the officer went to the family and offered condolences, went to the family and apologized, went to the victim and sought to offer first aid," the Rev. Keith Muhammad said.
When Mehserle wrote it on July 4 the jury had not yet decided his verdict; and if one is to believe thie letter, he wrote it independent of the trial's outcome.
The contents of the letter are very much in line with what he said on the witness stand, but he directed the words not at a jury, but to the general public.
"I have and continue to live every day of my life knowing that Mr. Grant should not have been shot. I know a daughter has lost a father and a mother has lost a son," he wrote. "It saddens me knowing that my actions cost Mr. Grant his life. No words can express how truly sorry I am."
Those words were the apology so many people had waited for, but according to ABC7's legal expert, the timing is suspect.
"I think the timing of this letter is extremely suspicious; it was written while the jury was out and after they had deliberated without returning an acquittal. Everything about this letter suggests to me that it's self serving," Dean Johnson said.
"It could have been sincere from his point of view, but from the point of view of the family, it should have taken place right after the shooting," Grant's family's attorney John Burris said.
In the letter, Mehserle said he hope to apologize to the family sooner but, "death threats toward my newly-born son, my friends, and family resulted in no communication occurring. I hope the day will come when anger will give way to dialogue."
"For now, and forever, I will live, breathe, sleep, and not sleep with the memory of Mr. Grant screaming, 'You shot me,' and me putting my hands on the bullet would thinking the pressure would help while I kept telling him, 'You'll be okay.'"
"If I were being very cynical about this, I would say that Mehserle has written down an expression of remorse for the benefit of the judge," Johnson said. "Remorse is a huge factor in determining the length of someone's sentence."
And so the contrast of what appears to be a simple, straightforward letter and all the interpretations of it.
As Mehserle says at the end, "I don't think I can ever convince some individuals how sorry I am for the death of Mr. Grant, but I would not feel right if I did not express my thoughts."