Los Angeles (CNN) -- Bobby Brown "is innocent until proven guilty" on a drunken driving charge that followed a traffic stop this week in California, his lawyer said. "Mr. Brown has not been convicted of anything associated with this incident," attorney Tiffany Feder said Tuesday night. "Mr. Brown is taking this matter seriously and an investigation is under way." Brown, 43, showed signs of intoxication and failed a field sobriety test during the traffic stop in the Reseda area of Los Angeles County, California Highway Patrol spokeswoman Tiana Reed said. "Mr. Brown was not driving erratically," his lawyer said. "He was speaking on his cell phone." He was "released on his own recognizance" after being charged, Feder said. Brown, the ex-husband of the late singer Whitney Houston, is scheduled to perform with his group New Edition on Thursday in St. Louis.
The singer "was not driving erratically," his lawyer says . Brown showed signs of intoxication and failed a field sobriety test, police say . Brown is Whitney Houston's ex-husband .