ST. PETERSBURG, Fla. -- Some civil rights and law enforcement leaders are calling for reform to Florida's "stand your ground" law after a controversial killing over a parking spot.

Michael Drejka claims he feared for his life before fatally shooting Markeis McGlockton last Thursday outside a convenience store on Sunset Point Road in Clearwater. The Pinellas County Sheriff's Office says McClockton shoved Drejka during a dispute over a disabled parking space, and that's when Drejka shot him.

Clearwater's police chief says the "stand your ground" law needs significant improvements. But a state lawmaker who drafted it says no.

"There is no need to change Florida's stand your ground law. There is a need, a crying need, to understand it," says Florida Sen. David Simmons (R-Orlando).

Simmons says a more thorough investigation is needed in the latest Clearwater case.

If Drejka is found to have initiated the altercation, he might not be able to use the self-defense law, Simmons says.

Criminal defense attorney Mark O'Mara, who defended George Zimmerman in the Trayvon Martin case, says in the Clearwater shooting, it's not clear that the law applies. 

He doesn't think McGlockton showed continued aggression after the push, but he says it's still a high burden for the prosecution to prove.

"My gut is it's a close enough call for the protections of the statute will be such that they will not file charges, but I like the idea of a grand jury to decide that," O'Mara said.

The State Attorney's Office is still reviewing the case.

Florida's "stand your ground" law recently changed so that the burden of proof now falls on the prosecution, not the defense.