A wig and mustache disguise didn't fool a Gwinnett County jury, which on Tuesday afternoon found Joanna Hayes guilty in the April 26, 2009 shooting death of her daughter-in-law.

Hayes was sentenced to life in prison with the possibility of parole for her conviction on charges of murder, aggravated assault and possession of a firearm. She'll be eligible for release in 30 years, according to current parole guidelines. However, those guidelines are subject to change depending on the state's prison population.

Hayes was sentenced to five years on probation after her release. Superior Court Judge Warren Davis also ordered her to have no contact with all but a few of the prosecution's witnesses. With the exception of her son and ex-husband, Hayes was barred from contacting members of victim's family, including her 3-year-old grandson. Hayes' son, Steven Strube, and Heather Strube were separated and getting a divorce at the time of the killing.

Hayes, dressed in a green silk dress with a black belt cinched at her narrow waist, maintained her innocence after the verdict. She displayed the only emotion she had shown during the trial when she addressed the judge before sentencing.

“I’ve never harmed anyone or anything in my entire life,” Hayes insisted, tears streaming down her face, her voice nearly inaudible at times. “It hurts me to hear others say that we had a strained relationship, because we did not… I did not commit this offense because I loved her just as much as anyone.”

But prosecutors said Hayes wore a "Sonny and Cher" style man's wig and fake mustache when she walked up and shot Heather Strube, 26, point blank in the head at the Target parking lot on Scenic Highway North in Snellville. Hayes allegedly wanted to avoid being recognized by onlookers as well as her grandson, who was then 18 months old. He was buckled into his car seat when his mother was slain outside her vehicle.

Strube's parents, Mary and Buddy Allen, got custody of her son following the slaying. The couple said they have lived each day in fear that Hayes might come after them, too. Hayes' conviction brought tears of relief to their eyes. A relative mouthed to Mary Allen "no more fear," after the verdict was read, and she nodded in response.

"I believe they convicted the right person," Mary Allen said later, outside the courthouse. "I will live my life cautiously. But we will live life, because my grandson deserves a full life."

Hayes' mother, Lois Hand,told reporters her daughter was a wonderful, loving person and that "a grave injustice was done today."

Strube's slaying was one of only four homicides in the history of Snellville. Snellville Police Chief Roy Whitehead and three detectives who worked on the case were seated in the packed courtroom when the verdict came down. The defense team had contended that police investigators jumped to conclusions when they charged Hayes, but Whitehead disputed that.

"We let the evidence take us to where we needed to go, to the person who committed that crime," Whitehead said.

A jury of eight men and two women spent two and a half days deliberating, jangling the nerves of prosecutors and defense attorneys alike. Assistant District Attorney, Christa Kirk, who prosecuted the case along with Deputy Chief Assistant District Attorney Dan Mayfield, said "we're very happy the jury took the time to look at it all."

"They did their job," Kirk said.