in another attempted murder trial. the trial is for john "hot boy" jones, who is charged with attempted murder after having allegedly shot a young woman in the face. on the stand is james mallory. >> nothing but the truth. >> yeah. >> mallory was released from prison on probation after prosecutors say he wrote them a letter stating he had bombshell evidence against jones. but today he's not testifying for the prosecution. he's been called to the stand by jones's lawyer. and now he has a very different story. >> did you write that letter? >> no. >> you didn't write that letter? >> no. >> it's not your handwriting? >> no. >> it's not your signature? >> no. >> in that letter you don't offer the commonwealth "bombshell evidence" on numerous cases? >> no. >> it's not your letter? >> i never spoke on this case either. >> though mallory, who had been