TAMPA, Fla. - A 47-year-old inmate walked free Friday after spending about 10 more years in prison than he should have because of an error by the sentencing judge.

Leonard Brown spent more than half his life behind bars after a judge sentenced him in 1982 to 99 years on a robbery conviction that allowed a maximum sentence of 15 years. A fellow inmate who once worked for a law firm discovered the error in Brown's file last year and helped him get it into court.