What is a stand your ground law?

Three different rules

• Duty to retreat. In a minority of states you must retreat if you can do so safely, before using deadly force outside your home.
• Castle doctrine. Nearly universal: no duty to retreat inside your own home, and in many states your vehicle or workplace as well.
• Stand your ground. No duty to retreat anywhere you are lawfully present.

What still has to be proved

The belief in danger must be both honest and objectively reasonable; the threat must be imminent rather than feared for later; and the force used must match the threat. Deadly force generally requires a reasonable fear of death or great bodily harm. A person who started the fight normally cannot claim the defence unless they clearly withdrew first.

Immunity hearings

Several states, Florida among them, allow a pre-trial hearing where a judge can grant immunity from prosecution, not merely a defence at trial. Where this exists, who carries the burden of proof at that hearing has been the subject of repeated legislative change, and it varies by state.

The civil side

These statutes often bar civil suits by the aggressor or their estate where the use of force was justified. But a criminal acquittal does not automatically end a civil claim, because the standards of proof differ.