KEEPING US UP-TO-DATE ON OFFICER BURKS AND ALL TO COME FROM THIS. I WANT YOU GUYS TO KNOW AT HOME, EVERY SINGLE DAY, NEARLY 1 MILLION POLICE OFFICERS ALL ACROSS THE COUNTRY, THEY GO OUT ON PATROL, AND MOST OF THEM ARE LIKE OFFICER BURKS, ALONE IN A SQUAD CAR. INVESTIGATIVE REPORTER BRIAN NEW HIS LIFE FOR US TONIGHT, LOOKING INTO THE CONTEXT OF WHY THIS IS AND WHETHER THAT PUTS OFFICERS AT RISK. >> Reporter: ALONE ON PATROL AT NIGHT. IT'S HOW MOST POLICE OFFICERS WORK. IT'S ALSO THE SITUATION OFFICER DARRON BURKS WAS IN WHEN HE WAS KILLED. ACCORDING TO A DEPARTMENT OF JUSTICE REPORT ON AMBUSHES AND UNPROVOKED ATTACKS, THE OVERALL NUMBER OF POLICE OFFICERS KILLED IS DECLINING, BUT THE PERCENTAGE KILLED DURING SURPRISE ATTACKS IS INCREASING. FROM 1987 TO 1996, 701 OFFICERS WERE KILLED. 11% WERE KILLED IN AMBUSHES. FAST FORWARD A DECADE, AND THE NUMBER OF OFFICERS KILLED THE CLIENT, BUT THE PERCENTAGE KILLED IN AMBUSH ATTACKS ROSE TO 21%. MORE THE -- THAN HALF OF THOSE KILLED, 57%, WERE ALONE IN THEIR VEHICLES. >> BELIEVE IT OR NOT , THERE IS REALLY NO EVIDENCE TO SUGGEST THAT HAVING TWO UNITS WOULD HAVE PREVENTED THIS FROM HAPPENING. >> Reporter: DR. ALEX DEL CARMEN SAYS AMBUSH ATTACKS ARE HARD TO PREVENT DUE TO THEIR UNPREDICTABILITY. HE SAYS DEPARTMENTS SHOULD FOCUS ON RESPONSE, ENSURING ENOUGH BACKUP OFFICERS ARE AVAILABLE AND STRATEGICALLY POSITIONED TO ARRIVE WITHIN SECONDS, NOT MINUTES. >> WE HAVE TO BUILD UP OUR PATROL FORCE. THAT IS THE MOST IMPORTANT PART OF ANY POLICE DEPARTMENT AND THERE ARE A LOT OF HOLES TO FILL. >> Reporter: IN AN INTERVIEW LAST YEAR, DALLAS POLICE CHIEF EDDIE GARCIA SPOKE ABOUT THE NEED FOR MORE OFFICERS. THE DALLAS POLICE DEPARTMENT HAS APPROXIMATELY 3100 SWORN OFFICERS WITH THE GOAL OF 3600 BY 2033. HOWEVER, MORE OFFICERS DOESN'T NECESSARILY MEAN MORE WILL PATROL IN PAIRS, NOR DOES IT MEAN BACKUP WILL BE IN CLOSER IF THE CITY CONTINUES TO GROW. WHAT WOULD PREVENT THAT PERSON FROM AIMING AT TWO PEOPLE VERSUS ONE? >> OUR FEELING THAT TWO PEOPLE IS BETTER THAN ONE, BECAUSE THEY ARE GOING TO BE ON THE LOOKOUT FOR ONE ANOTHER IS GREAT, BUT THE NUMBERS, THE SCIENCE, THE RESEARCH IS NOT SUPPORTIVE OF THAT RIGHT NOW. >> Reporter: WE HAVE SEEN OVER THE YEARS, DEPARTMENTS PAIR UP OFFICERS AFTER A MAJOR INCIDENT. WE SAW THIS IN 2016 AFTER THE AMBUSH HERE IN DOWNTOWN DALLAS THAT KILLED FIVE OFFICERS. BUT, THESE ARE, TYPICALLY, TEMPORARY. TODAY, MOST DEPARTMENTS ACROSS THE