Police are submitting information about the case to the Brookings County state's attorney for a final decision on whether charges will be filed.
Two statutes under South Dakota law address justifiable homicide.
In one case, state statute 22-16-34, it's justifiable to kill someone who is trying to kill you or commit a felony against you or in your dwelling.
The second statute, 22-16-35, says homicide is justifiable in defense of other people in a household if there is a reasonable belief that a felony is going to be committed or that someone is in danger.
While state law allows for the use of lethal force in certain situations, people must have a "reasonable and good faith belief" that another person is about to commit a felony against them, said Richard Travis, a lawyer for May & Johnson in Sioux Falls and former president of the South Dakota State Bar Association.
"I don't think that state law provides for the idea that just because somebody comes into your house ... that you can just shoot them," he said.
State law, however, does not list criteria for what would meet the reasonable and good faith belief, Travis said. And the use of lethal force might not be justified if it's considered excessive given the threat a person is facing, he said.
"A jury has to focus on what they believe or put themselves in the shoes of the defendant and decide whether they think the defendant's actions were reasonable," Travis said.