From the New York Times, I'm Michael Barbarale. This is the Daily.

Today, the AR-15 rifle used in the Florida shooting was legally purchased by the Teenage Gunman.

How did a semi-automatic weapon originally designed for American troops to kill enemy fighters become easier to buy than a handgun?

It's Friday, February 16th.

Are you Nicholas Jacob Cruz?

Yes, ma'am.

Okay, sir. You are charged with 17 counts of pre-meditated murder.

State, how would you like to proceed today?

You're on the state's relying on the sworn-out of David that the court has been provided as to the 17 counts of first-degree murder

and the contents of the sworn-out, David by detective, citing the actions of the defendant and going to Marjorie Stoneman Douglas High School on February 14th, 2018, with a pre-meditated design in that he went loaded with an AR-15 rifle.

Chris, where did this gun, the AR-15, where did it come from?

Well, it has a complicated history that reaches back to Cold War arms design.

Chris Chivers is an investigative reporter for the times.

In the 1950s, the United States had selected another rifle for its armed forces to use a standard rifle.

The M-14, about 11 pounds, when combat loaded, firing a 7.62-millimeter NATO cartridge easily converted to automatic fire.

But a company called Armolite in Southern California designed a competitor weapon, a prototype called the AR-10.

It didn't do well, the Army wasn't pleased with it, but an Army general was involved in the military.

And he was called the AR-15.

He was called the AR-15.

And it's worth noting that the AR-15 was at first a failure. It didn't really have any customers.

The breakout really came in 1962.

The American soldiers hiking their way through the sweaty jungles of South Vietnam.

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