Story highlights Martin's family: "Arrest of admitted killer is not a violation of due process, it is due process"

A year ago, George Zimmerman was arrested in the death of Trayvon Martin

Zimmerman's mother: "The justice system failed us as Americans"

George Zimmerman, charged with murder, says he shot Martin in self-defense

In a scathing letter released on the anniversary of George Zimmerman's arrest in Trayvon Martin's shooting death, Zimmerman's mother writes that her son was charged "solely to placate the masses," and that the news media helped pass on a false narrative against an innocent man.

"April 11, 2012, will be forever remembered by the Zimmerman family as the day the justice system failed us as Americans, and as a consequence an innocent man was arrested for a crime he did not commit, solely to placate the masses," Gladys Zimmerman wrote.

Authorities say George Zimmerman, a neighborhood watch volunteer, shot 17-year-old Martin in Zimmerman's neighborhood in Sanford, Florida, in February 2012.

Zimmerman is awaiting trial, charged with second-degree murder in Martin's death.

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He claims he shot Martin in self-defense after Zimmerman saw the teenager acting suspiciously in the neighborhood. Zimmerman told police that the two exchanged words and Martin went after him. According to his account, the teen -- who was unarmed -- punched him, forced him to the ground and slammed his head on a sidewalk.

Attorneys for Martin's family have accused Zimmerman of racially profiling the 17-year-old and shooting him "in cold blood."

Gladys Zimmerman's letter is critical of those attorneys for the Martin family, claiming they manipulated "perception in order to sway the 'court of public opinion.'" She contends that a vast amount of evidence released since the shooting supports her son's self-defense claim, but most media outlets have avoided its publication and turned him into a "mythological monster."

In response to the letter, Martin's family members and their attorneys released a statement saying, "For the Zimmerman family to allege that the justice system doesn't work, simply because they are unhappy their son was arrested in the first place, is disingenuous and disrespectful to the very system that is currently affording him every available opportunity to defend himself."

The statement continued, "The arrest of an admitted killer is not a violation of due process, it is due process."

Addressing supporters, Gladys Zimmerman wrote about her son's trial, set for June: "My son has always told the truth and your trust is well-placed. The upcoming trial will not disappoint you."

Meanwhile, a financial update posted Thursday on the website for the Zimmerman Legal Defense Fund Trust said the defense "is now running at a deficit, and it is unclear how the defense will be funded moving forward."

According to the update, since March 3 the fund raised $14,458.63 to help pay for Zimmerman's defense. "Current liabilities exceed cash on hand by about $10,000," the update said.

The site said from the time the fund was established last May 2 through January 3, more than $314,000 was raised for Zimmerman's defense.