Some 24 states followed Florida in putting Stand Your Ground laws on their books, at least ten of which are nearly identical to the measure that’s gained national attention after George Zimmerman, 28, shot and killed 17-year-old Trayvon Martin in Sanford, Fla., last month and was not arrested because he said he was acting out of self-defense.

In 2005, Florida passed its Stand Your Ground law, which offers legal immunity to individuals who use deadly force when they believe they are being threatened by another. The National Rifle Association pushed the legislation through state legislatures across the country as an expansion of the nation’s gun rights laws.

After Florida passed its law, the American Legislative Exchange Council (ALEC) adopted its legislative language as one of the model bills it proposes to legislators across the country on behalf of its member associations, in this case the NRA.

A Sunlight Foundation analysis using automated textual analysis  found that not only are the laws similar, but at least 10 of  the states based their legislation on nearly identical bills to the one Florida passed and ALEC adopted.

Because some states do not make the original legislation available online, there could be even more states that used what became an ALEC model bill to guide their legislation.

The analysis was able to detect striking similarities and identical phrases across multiple bills, including the phrase, “[a] person is presumed to have held a reasonable fear of imminent peril of death or great bodily harm to himself or herself or another when using defensive force that is intended or likely to cause death or great bodily harm …,” which is just one of the provisions of the law that is intended to protect people who may have killed another person from being arrested or prosecuted.

Michigan’s House Bill 5153 that passed the state legislature in 2006 was the most similar to Florida’s bill, according to the analysis. When compared to the Florida bill it returned the highest rate of matches than any other bill did at 146 fragments matched. The state bill with the lowest matching rate to Florida was Mississippi Senate Bill 2426 at 20 matching fragment counts.

The ten states that were revealed to have varying degrees of similarities to the Florida bill are:

• Michigan
• South Carolina
• West Virginia
• Kentucky
• Oklahoma
• Tennessee
• Wisconsin
• Wyoming
• Kansas
• Mississippi

The NRA hasn’t commented on the Martin case specifically, but has said the Stand Your Ground law is good legislation and to call it otherwise would be a mistake.

Florida State officials have said that it will be more difficult to prosecute the shooter, George Zimmerman, if they decide to do so, because of the law.

Breanna Edwards contributed to this post.