Leone said in a telephone interview yesterday that the SJC had struck the proper balance between the right to self defense and the right of society to prevent tragedies — such as a child mishandling a loaded firearm.

“What they did for us as a state is they allowed us to continue to engage a balance between how we provide for our own self-defense and how we . . . avoid tragedy, especially when guns are in the hands of those who shouldn’t have them,’’ Leone said.

The unanimous decisions by the SJC flow from a landmark ruling by the US Supreme Court in 2008, in District of Columbia v. Heller.

The Supreme Court said for the first time that the US Constitution’s Second Amendment protects an individual’s right to own a firearm for self-defense, but the court limited the reach of its ruling to “federal enclaves’’ like the District of Columbia.

Last week, the Supreme Court heard oral arguments in a gun ownership case in Illinois in which, legal specialists say, the court is likely to determine whether the Second Amendment will now be explicitly extended to the states — and state laws and regulations set up to control the use, sale, and storage of firearms.

In yesterday’s SJC cases, Justice Gants wrote that an 1875 US Supreme Court ruling (called Cruikshank) remains in force and gives Massachusetts the authority to chart its own course when it comes to regulating firearms and ammunition.

“Under Cruikshank, the Second Amendment imposes no limitations on the ability of the Massachusetts Legislature to regulate the possession of firearms and ammunition,’’ Gants wrote. “These cases are the law of the land until the Supreme Court decides otherwise, and we are therefore bound by them.’’