Mehserle's attorney released the hand-written letter Friday. In it, Mehserle said he wanted to reach out Grant's family in the days after the New Year's Day 2009 shooting but could not because of death threats.
Grant's family took issue with the timing of the letter and the fact that it was not addressed to the family.
"This was a letter that was purposefully designed to influence the judge as well as the jurors to bring about what he got. Sadly to say, we're not buying it as a letter of apology to us and the public does not believe it, as we don't," Grant's uncle Cephus Johnson said.
Johnson says the apology should have been directed to Grant's relatives and it should have come 19 months ago when Grant was shot at the Fruitvale BART station.
In the letter, Mehserle says no words can express how sorry he is, but he doesn't directly address the Grant family.
Johnson calls Mehserle's letter garbage.
"Just like he fake cried on the stand, he sent out a fake letter to the public and nobody is fooled by this letter," Johnson said.
Johnson spoke while surrounded by people who have supported him and the family since the shooting. Grant's mother, Wanda Johnson, listened-in but was too upset to speak. Her brother thanked everyone for standing by them and promised that the fight is far from over, saying the family is disappointed in the involuntary manslaughter verdict.
"And we're strategizing now some efforts to bring about some real serious charges from the Department of Justice," he said.
Immediately after the verdict, the family called for peaceful protests and most demonstrators honored that request. But late Thursday night, pockets of violence erupted resulting in the vandalism of 100 businesses. A reporter asked Johnson for his reaction.
"The coalition of activists that has embraced and supported us demonstrated in a peaceful non violent way," Johnson said.
One of his supporters took issue with the question.
"It is unfair to put the weight of the violence in the community on the shoulders of the family of Oscar Grant," said Rev. Keith Muhammad. .
Johnson told ABC7 he would like to see Mehserle tell the judge to give him the maximum sentence, so he can show the public and Grant's family that he really is sorry.
Mehserle was convicted of involuntary manslaughter relating to Grant's death and is in custody awaiting sentencing.