The Brief Colin Gray, father of Apalachee High School mass shooter Colt Gray, faces up to 180 years in prison at his sentencing in Barrow County. Prosecutors proved the 55-year-old ignored mental health warning signs and gave his 14-year-old son the weapon used to kill four people and injure 11. A judge delayed the sentencing for months while waiting for the teenage gunman's legal proceedings to conclude with a life sentence earlier this week. The father of Apalachee High School mass shooter Colt Gray will appear in a Barrow County courtroom Thursday for his sentencing. What we know: Colin Gray, 55, faces a maximum sentence of 180 years in prison after a jury convicted him in March on 27 counts, including second-degree murder and involuntary manslaughter. Prosecutors argued that the father failed to act on obvious mental health warning signs involving his son, who was 14 at the time of the tragedy. Despite those warning signs, Colin Gray provided his son with the AR-15 style assault rifle used in the attack that left two students and two teachers dead, as well as 11 people injured. PREVIOUS STORY: Apalachee HS shooting: Colin Gray sentencing date set The court delayed Colin Gray's sentencing after his March conviction to wait for the resolution of his son's case. Legal experts noted that Colin Gray's crimes directly linked to his son's actions in a unique way for Georgia courts. Colt Gray's case concluded Tuesday when he pleaded guilty to all 55 counts and received a sentence of life in prison without parole. What we don't know: Court officials have not yet confirmed the exact sentence length the judge will issue during Thursday's proceedings. #fox5atlanta #crimewatchatlanta