ST. LOUIS COUNTY, Mo. -- Rodney March II has been charged with one count of endangering the welfare of a child in the first degree, KTVI reports.
He is being held on $100,000 cash only bond.
St. Louis County police say he left a loaded .40 caliber glock within reach of his 3-year-old son, Rodney March III, who shot himself in head.
Officers tried to save his life but the child was pronounced dead at the hospital.
"What is really hard for us is that we know that these deaths and injuries from unintentional shootings are 100% preventable when guns are secured safely," said Lisa Bernstein, with Women's Voices Raised For Social Justice
The shooting happened around 11:30 a.m. Thursday.
The three-year-old boy was home with both parents at the time.
Bernstein says her volunteer group, WVRSJ, has conducted 200 gun safety teaching lessons in the St. Louis community.
"We just encourage people to follow common sense safe gun storage rules. So that if a child gets a hold of a gun, it's secured and cannot be used," Bernstein said.
Rodney march III is one of many children who have lost their lives due to an unintended shooting death.
Bernstein says one reason people don't secure their guns at home is because they don't feel they can use it quickly if needed.
However, she says statistics show you are more likely to be injured with your own gun than being able to defend yourself.
"This family of the 3 year old will be forever changed and the community around him," Bernstein said.
Parents are not always charged when their children find and use a gun, even if it results in death.
Just 27 states and the District of Columbia have laws regulating children's access to guns and only 15 of those states impose criminal punishment on people who store firearms negligently.