The debate over controversial “stand your ground” laws is heating up again, as lawmakers in at least two states are seeking to expand protections for people who commit violence in self-defense.

On Wednesday Republican state lawmakers in Iowa advanced a bill to enhance existing “stand your ground” laws. By a party line vote of 13 to 7, Republicans on the House Judiciary Committee voted to send House Study Bill 133 to the full House floor for debate. The proposed legislation would expand to public spaces the “castle doctrine” — the plank in English common law that holds that a person can defend his life with lethal force if necessary when an intruder enters his home or property.

Currently, Iowa law says people must exhaust other ways of achieving safety if they feel their life is at risk when in public.

Under Republicans’ proposed changes, people would not have to exhaust lesser means before using deadly force if they feel their life is at risk.

“It is about the right to self-preservation,” Republican Rep. Matt Windschitl said in a Wednesday House committee meeting. “This is about making sure Iowans [who] find themselves in a situation where they have to make a snap decision that they don’t have that fear in the back of their mind of being prosecuted, taken to court and losing a whole bunch of money on attorneys’ fees and time out of their life when they were justified in defending themselves or another person.”

David Walker, a retired Drake University Law School dean, testified, however that Iowa’s “castle doctrine” already lets Iowans use deadly force if they reasonably believe their life is endangered in their home or car.

Some of Iowa’s black residents have expressed concern that law’s expansion would bring more violence, not less.

“That is highly concerning to me, because I could just possibly walk in a room, somebody could be afraid and they feel threatened, and I’m on the ground with a bullet in my chest,” Renaldo Johnson testified at a recent House hearing, according to the Des Moines Register. “Just because they are afraid, they can kill someone,” he said of his neighbors.

“I’ve watched my son walk from the back of my house to the front of my house and be stopped by a police officer because he fits the bill of ‘that kid,’” Des Moines resident Laural Clinton testified. “I’m a parent, and this law scares me.”

Clinton told the House panel, “I’m not anti-gun. I’m anti-stand your ground.”

The Republicans proposal also lets citizens who believe they are “adversely affected” by any new guns-free zone on state or local government property to sue for damages.

In Florida, Republican lawmakers want to change their state’s existing “stand your ground” law so that prosecutors must prove a defendant wasn’t acting in self-defense before a case can proceed to trial, a measure being decried by law-enforcement and gun-control critics.

The change to the Sunshine State’s 2005 law would shift the burden of proof from defendants to prosecutors during the pretrial phase of court proceedings in cases in which the defendant has invoked self-defense.

Florida’s existing “stand your ground” law received worldwide scrutiny after the 2012 killing of unarmed black teenager Trayvon Martin by an armed neighborhood watchman George Zimmerman.

Although the law was not ultimately used in Zimmerman’s defense, his trial and eventual acquittal brought to light the state’s uneven application of the law.

After Martin’s death, the Tampa Bay Times conducted an investigation of almost 200 “stand your ground” cases and found the number of such cases is increasing in recent years “largely because defense attorneys are using ‘stand your ground’ in ways states never envisioned.” The paper noted that defendants invoking stand your ground defenses “are more likely to prevail if the victim is black” and that blacks who use “stand your ground” defenses are almost 15 percent more likely to face a penalty for doing so than their white peers.

Marissa Alexander, an African-American woman whose “stand your ground” defense against a husband with a history of abuse was denied by a judge during a pretrial hearing, has supported Republican efforts to change the law.

“Here is a black woman who had a history of abuse against her and tried to use stand your ground and ended up with a 20-year sentence,” Bruce Zimet, one of Alexander’s lawyers recently told The New York Times. Alexander told the Times she believes the “stand your ground” law “was never considered” by her judge. She spent almost half a dozen years in prison or confined to her house after she was convicted of aggravated assault charges in 2012 for firing a warning shot at her husband. Her conviction was overturned on appeal in 2013.

Florida was the first state to pass a “stand your ground” law, in 2005, with strong support from the National Rifle Association. According to the American Civil Liberties Union, 23 other states have such laws.