Special Weapons and Tactics, or SWAT teams, respond often to deadly situations.
"It's not like the police all of a sudden decided one day we wanted to roll around in armored bulletproof vehicles and carry long rifles and wear these flack vests that stop bullets," said Richard Bryan.
Bryan, with Alamo Area Council of Governments, offers police training for cadets and seasoned officers.
"With Special Weapons and Tactics, one of the things we teach is you're going to be challenged. Where things are going chaotic and things are going bad, you need to know what your limitations are,” said Bryan.
In 1966, a 96 minute rampage from the top of the University of Texas tower left 15 people dead. Marine-trained Charles Whitman shot his victims from a 300 foot perch at the top of the tower.
Whitman had 7 guns that day, including three high-powered rifles.
Click here for more of our special coverage from the 50th anniversary of the UT Tower Shooting.
Los Angeles saw incredible violence in the mid-60s as well, including the 1965 Watts riot where 1,000 people were hurt, and 34 killed.
"At that point we realized we needed some type of a force which has the ability to counter suspects who were in hardened locations,” said Scott Reitz.
So while Austin police were busy trying to stop the ex-Marine, LAPD was already developing new training methods.
"Initially some of the training, I understand, was provided by the Marine Corps," said Reitz.
By 1968, SWAT was born in Los Angeles, the first in the nation.
13 years after the UT shooting, APD launched its SWAT Unit.
"You're going to have incidents where it requires highly-skilled, highly-trained, well-equipped individuals," said Reitz.
SWAT experts say every incident spurs new techniques and a need to be better equipped.
"And if you don't have a response team that can meet the challenge, then you're going to look at mass casualties,” said Reitz.