By Amy Lester, NEWS 9

OKLAHOMA CITY -- An Oklahoma City pharmacist is now facing first-degree murder charges after fatally shooting one of the two robbers that struck his store May 19.

This incident has a lot of gun owners asking what they can or cannot do under Oklahoma law.

The law is not totally black and white. Even people well versed in it have opposite opinions when it comes to this murder charge.

Andy Coats, Dean of the University of Oklahoma Law School, is a former Oklahoma County prosecutor familiar with state gun laws.

"I thought the District Attorney had a very hard decision to make, but it's one of those things, the law has to be honored and followed," Coats said.

Coats believes the pharmacist, Jerome Ersland, broke the law.

Oklahoma State law says a person must have "reasonable fear of imminent peril." Only then does that person have the right to "stand his or her ground and meet force with force, including deadly force, if he or she reasonably believes it is necessary to do so to prevent death or great bodily harm..."

"Once that's over with and there's no threat left to anybody, it's very difficult to justify going out and firing into a person who's either wounded or dying," Coats said.

The main question is whether Ersland was still under a threat when he returned to the store and fired five more shoots at the teen, lying on the ground.

"I just think it's ludicrous to charge a man with first-degree murder," said Miles Hall, owner of H&H Gun Range.

Hall teaches conceal and carry classes at his store.

"We teach that the aspect is you shoot to stop the act of aggression," Hall said. "Once the act of aggression is stopped, you're through, but you know, we don't really know everything there is to know about this. There's a lot you can't see in the film footage."

Hall believes the pharmacist still felt there was a threat when he got a second gun and started shooting.

"What I may consider as not threatening, you might consider as actually being threatening and so that really is an interpretation to the individual," Hall said.

An interpretation of the law will take place in the courtroom, as Ersland defends himself against his charges.

Representative Randy Terrill (R-District 53) said if Ersland is convicted of first-degree murder, the lawmaker will take a second look at how the law is written.

"If this first-degree murder charge sticks against the pharmacist, who was merely defending himself and the other women who were there in the pharmacy, I think it may very well call for lawmakers to revise the Stand Your Ground Law," Terrill said.

Representative Terrill was one of the authors of the "Stand Your Ground" law and said that law is why Ersland shouldn't be facing criminal charges.

"I know David Prater and I like David Prater, but I think the fact that he's brought a first-degree murder charge against this pharmacist is absolutely insane," Terrill said.

Representative Terrill said the "Stand Your Ground" bill he helped sign into law three years ago should protect this pharmacist from prosecution.

A number of legislators are already discussing the possibility of re-working the law in the next session if Ersland is found guilty of murder.

While some lawmakers are gearing up for action, others feel it's too soon.

"There is something the public doesn't know and that's why he filed these charges," said Representative Richard Morrissette (D-District 92). "David Prater is sworn to uphold the law as it exists."

In his news conference Wednesday, Prater made it very clear he is a supporter of the state's "Stand Your Ground" law, but did say the law has limitations.

There were a total of nine lawmakers who voted against the "Stand Your Ground" law in 2006.

One of those lawmakers, Representative Jim Wilson said he's pleased to see police and prosecutors are taking what he calls a "dangerous law" seriously, and not just letting people go around shooting one another.

Coats said the law is clear, but will ultimately be decided in court.

"It is as clear-cut probably as it can be written," Coats said. "There are just areas in the law that you just can't write down that have to be decided by judges and juries."

Coats and Hall both said people should not be afraid to protect themselves because of this case.

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