Families of three murder victims in Wednesday's brutal attack at a Florida bank have opted not to publicly release the names of their loved ones - a major test of a controversial amendment that is gaining momentum and legal challenge around the nation.

Florida and at least five other states in the last year have passed some form of Marsy's Law, which aims to provide broader rights to victims and their families. The laws have become a hotbed of national controversy over whether they overreach and violate basic constitutional guarantees of open information, as well as legal rights of defendants.

Florida's version of Marsy's Law went into effect earlier this month and has already had a chilling effect on what usually is basic public information: namely, the release of victims' names.

"Police departments have withheld information because they're not sure and are going over and above," said Jeanne Hruska, policy director of the ACLU of New Hampshire, who has done extensive research on Marsy's Laws around the country. Police departments, she said, have brought different interpretations of the law's language.

Police say families of the five victims in Wednesday's attack at a SunTrust Bank had the right to withhold their murdered relatives' names under Amendment 6, approved by Florida voters in November. Three of the families opted not to release names of their relatives; the other two families allowed police to release names, according to Sebring Police Chief Karl Hoglund.

“We felt it was time that the victims had the same clear protections for victims as the accused,” said Jennifer Fennell, spokesperson for Marsy’s Law for Florida. “It doesn’t seem to me that there should be an automatic right for the public to know a victim’s name or gender. The identity of the victims could be used and has been used in the past to intimidate and harass victims and families.”

The Associated Press reported late Thursday that two of the three remaining victims' names have been released by relatives. Hoglund cited the new Florida law as the reason why police did not release the names.

The ACLU and others have argued that Marsy's Laws, while well-intended, go too far and may even infringe on rights of defendants. Since the amendment took effect on Jan. 8, several Florida police agencies have stopped releasing basic information about crime victims.

Florida bank shooting victims:4 employees and 1 customer, are all women

Police in in the state capital of Tallahassee provided sparse details about the victim of an apparent traffic crash in which a body was found in the middle of a neighborhood roundabout. Similarly, Tampa authorities declined to provide information about two people found shot dead in a car near the Busch Gardens theme park.

In both instances, police cited a provision in the amendment to protect the victim's right "to prevent the disclosure of information or records that could be used to locate or harass the victim or the victim's family or which could disclose confidential or privileged information of the victim."

In all, there are now 11 states - including California, Ohio, Georgia, Illinois and Kentucky - that have adopted Marsy's Law, named after a murder victim whose family was confronted by an accused killer at a supermarket after making bail.

In South Dakota, which passed a form of Marsy's Law in 2016, a state trooper and a sheriff's deputy both invoked their right to privacy under the law after shooting criminal suspects. They argued successfully that their names should be withheld from the public because they were crime victims and therefore the government had no right to release their names.

Who is Zephen Xaver?:Who is Zephen Xaver, suspect accused of killing five at SunTrust Bank

Actor Kelsey Grammer has been a staunch advocate for Marsy's Law nationwide. The actor’s father, Frank Allen Grammer Jr., was murdered in his home at age 38 and his sister, Karen Grammer was raped and murdered at 18.

“When my father’s killer was released and allowed to live out his days in freedom, we were never told,” Grammer said in a video on Marsy’s Law for All’s Youtube channel. “I found out through the National Enquirer. It seemed like a cruel joke.”

Tallahassee Police Chief Michael DeLeo says that the Florida law could mean redacting information ranging from crime scene addresses to perpetrator identities.

“It’s a very broad protection that’s been granted to victims and their families, and we’re trying to make sure we honor the spirit of what people voted for,” DeLeo said. “It restricts the amount of information and the detail of information that we may have been able to provide in the past.”

Marsy's Laws have received heavy economic boosts from noted billionaire Henry Nicholas, who shaped and named the movement after his murdered sister Marsy, who was killed by a jealous boyfriend in Malibu, Calif. in 1983. California passed its Marsy's Law in 2008, and since then, Nicholas has used part of his fortune to crusade for privacy rights of victims around the country.

Contributing: Florida Today; Tallahassee Democrat.