Zimmerman's brother goes on Twitter tirade in Trayvon Martin case By Barbara Liston ORLANDO, Florida (Reuters) - The brother of the Florida man charged in the shooting death of teenager Trayvon Martin took to Twitter to criticize a lawyer involved with the case, which could complicate the accused murder's legal defense. Robert Zimmerman Jr., whose brother George Zimmerman faces up to life in prison, recently appeared on several TV and radio shows complaining about a "vast mis-information campaign," as well as highlighting an "official letter of condolence" to Trayvon Martin's family. George Zimmerman, who is white and Hispanic, is charged with shooting and killing the unarmed, black Martin as he walked through a gated community in Sanford, Florida, in February. After Robert Zimmerman Jr. appeared Monday on CNN's Piers Morgan Tonight, an Orlando civil rights lawyer Natalie Jackson suggested the family was using the media for fundraising. Jackson was one of a group of lawyers and supporters who helped bring public pressure to bear on police and prosecutors for not immediately charging Zimmerman after he shot 17-year-old Martin. Jackson's comment prompted a twitter tirade by Robert Zimmerman Jr. who wrote to Jackson: "My Life's work = you WILL be held accountable for your words/actions. I will see U disbarred. George Zimmerman has said the shooting was self-defense and justified under Florida's "Stand Your Ground" gun law. "We're naturally concerned about anyone associated with the case speaking publicly, because there is always a risk that their comments could complicate our defense efforts," Zimmerman's lawyer Mark O'Mara told Reuters in an emailed statement. O'Mara previously called "ill-timed" a book and television appearances in September by George Zimmerman's friend Mark Osterman. Osterman revealed details of the shooting that he said were drawn from conversations he had with Zimmerman and his wife while they stayed in his home for several weeks after the killing. Benjamin Crump, an attorney for the Martin family, said the tweets by Robert Zimmerman Jr. could play into the hands of prosecutors if he is called as a witness. Robert Zimmerman Jr. is one of several friends and family members who say George Zimmerman told them what happened the night of February 26 when he killed Martin. Prosecutors could use that in court as they claim Zimmerman has not been consistent with his version of events. "When they go to testify your character and your credibility is at issue so I think these (Twitter) comments could have an effect," Crump said. Editing by David Adams and Lisa Shumaker