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(CNN) —

Cases of self-defense aren’t always simple – especially in states with a “stand your ground” law.

In July 2018, police say Michael Drejka fatally shot a man who shoved and knocked him to the ground in an argument over a parking space in Florida.

Although critics say Drejka’s use of deadly force was uncalled for, the Pinellas County sheriff declined to arrest him, citing the state’s “stand your ground” law, which gave him immunity. The decision sparked outcry and calls for reform.

But it’s not the first time a “stand your ground” law has created controversy. Many states have similar laws on the books.

Here’s what you need to know about them.

What is a ‘stand your ground’ law?

Generally, “stand your ground” laws allow people to respond to threats or force without fear of criminal prosecution.

Most self-defense laws state that a person under threat of physical injury has a “duty to retreat.” If after retreating the threat continues, the person may respond with force.

“If you attack me in a non-’stand your ground’ state, I’ve got to try to get out of it,” explained CNN legal analyst Mark O’Mara. “I have to retreat before I attack … The theory is, it (responding with force) has to be your last chance.”

“But in ‘stand your ground’ states, you have no obligation to retreat,” O’Mara said.

In other words, someone facing an imminent threat can use lethal force right away – without first trying to escape.

01:56 - Source: CNN

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