Tyrone Brown, the Dallas man sentenced to life in prison in 1990 for smoking a joint while on probation for an armed robbery in which no one was injured, walked out of prison in Huntsville Thursday after receiving a conditional pardon from Texas Gov. Rick Perry (R). The pardon came after ABC News' 20-20 featured his story twice, helping to create a nationwide grass roots effort to win his freedom, Save Mr. Brown.

Brown was met by relatives and journalists, according to an Associated Press report filed from Huntsville. He broke into a broad smile as he embraced his mother, Nora Brown. "I didn't believe this day was going to come," he said.

Under the terms of the pardon, Brown will have to live with his mother, find a job, go to a therapist, and report to a parole officer. If he violates any of those conditions, the pardon could be revoked.

Brown was 17 when he was convicted of armed robbery. After he tested positive for marijuana once, Judge Keith Dean re-sentenced him to life in prison. The harshness of Judge Dean's sentence for Brown, which he has never explained, stands in sharp contrast to his treatment of well-connected, white John Alexander Wood. Wood was convicted of murder, but Dean sentenced him to probation, where he repeatedly tested positive for cocaine. But instead of sending him to prison, Dean gave him permission to quit reporting to his probation officer and quit taking drug tests.

With the glare of the national spotlight on the case, Judge Dean (by now ex-Judge Dean) joined a long list of local law enforcement officials calling on the governor to free Brown. Thanks to their efforts, as well as the efforts of muckraking media outlets and an aroused populace, one drug war prisoner has gone home. That leaves about 499,999 to go.