Christopher Barling has been working with the Los Angeles police department's homicide division since 1993. He's now the homicide supervisor for the 77th division in south LA, which has historically had one of the highest murder rates in the city.

As a part of our 'A day's work' series, Detective Barling has agreed to open up about his life and his work with Guardian readers, and answer questions throughout the afternoon. So what do you want to know? Leave your questions below and Detective Barling will be online after 2pm ET | 7pm BST to respond.

What's a typical day like for you?

First of all, there is never a typical workday for a homicide detective. I work what's called a 9/17 shift, which means that I work nine-hour days, nine out of 10 weekdays, with weekends off. However, since I am the homicide supervisor, I am always on call.

I usually start my day between 6-7am, depending on the LA traffic. First thing I do is meet with the members of my squad, as they get their morning cups of coffee. I then transition the conversation into getting updates on their current investigations and their investigative plans to solve their cases.

Next, based on the teams of detectives' availability, I determine who is going to be on call with me during the week (they get to pre-schedule what weekend they have in advance). I then usually do a series of administrative functions: completing time sheets, signing overtime slips, reviewing search warrants, court orders, etc. But that's only the case if we didn't have a homicide overnight.

When a murder occurs it is rarely during business hours; it is usually between 10pm and 3am. So, on those days, my watch officially starts when I arrive at the crime scene. I then assess if more detectives need to be called in to start early and start handing out tasks to be completed. Some of tasks can be locating and interviewing witnesses, re-canvassing the crime scene for additional witnesses or evidence, locating and downloading surveillance footage, booking evidence, searching through criminal data bases, and meeting with other law enforcement officers, who have expertise in the area where the crime occurred.

I oversee all of this and monitor the investigative team who is assigned the case and the teams that are assisting them. I also meet with the area captain and the bureau chief and update them on the status of the case to help assist them in the assignment of uniformed officers in the area for future crime prevention and apprehension. I also meet with gang intervention personnel and discuss the potential of retaliation because a high number of the murders in 77th division have some relationship to street gangs. The victims are not always gang members but the suspects usually are. All of this tends to make for long days and end of watch is rarely what it is scheduled to be.

What makes for a really good day on the job?

I am fortunate that every day is a good day on the job. I have the privilege of working with and supervising arguably the best detectives in the world. What makes a special day, is watching the detectives put together their cases and solving them. It is satisfying to watch a team of detectives getting excited that they just got their suspect identified or have a enough evidence to file a case against a murderer. If I am to use an old cliché, as homicide detectives we get to speak for the dead. It is exciting to watch a detective interviewing a suspect, and getting that suspect to make admissions or confess to a murder. It is also rewarding to hear one of the detectives get the call from the district attorney that a jury just convicted a suspect who is responsible for a murder. These days are special because we can then explain to a family that we know who is responsible for killing their loved one.

How long have you been a homicide detective? What's changed over that time?

I began working as a homicide detective in 1993, and technology is the biggest change over that time. When I first started working cases, we didn't have computers. We use to handwrite all reports and then typed them on a typewriter. Now everything is done on a computer. In 1993, we just had blood typing that was used to help identity people to a crime scene. Now DNA is used, which can identify an individual using his DNA to one in a billion, quadrillion or greater. There was no social media or surveillance cameras. The technology of today has greatly helped detectives build circumstantial evidence in their cases. We now also pass information out on Twitter on @LAPD-CGHD, @LAMurderCop and @77thHomicideCop.

Please remember, real detective work is not what you see on television shows like Law and Order, CSI and Dexter. We usually don't solve a case in an hour, or find scientific evidence everywhere.

What are the most difficult aspects of your job?

Over the past 10 years, 77th division has had 549 murders and there are approximately 250 open cases which are still not solved. Homicide detectives tend to be some of the most committed officers in any police agency and never want to go home without solving their case. But truth be told, we can't solve a case without the community's help and not every homicide case gets solved. However, just because it isn't solved does not mean that it is not being worked. Every year detectives solve anywhere between 60-70% of the cases, but only about 30-40% are from that calendar year. The rest of cases, which make up the difference, are from the previous years' cases.

Tell us about a case that had a big impact on you in the last few years:

All of the cases that you work or respond to affect you in some way or another but recently in 2010, there were two cases that stood out.

They were the senseless murders of Aaron Shannon Jr and Kashmier James. Aaron was a five-year-old boy, who was shot to death on Hallowe'en night in his grandfather's backyard while wearing his Hallowe'en costume (a Spiderman suit). Kashmier was a 25-year-old mother, who was standing near her car on Christmas night with her three-year-old daughter seated inside, when the suspect, who was standing down the street shot and killed her. In both of these cases, neither victim nor their families had anything to do with gangs.

Thankfully, the detectives who were assigned to both of these cases have arrested the suspects who were responsible for the murders. Both of the cases affect me in a couple of ways. One is just to be grateful of every moment I spend with people and my loved ones, because life can end so short and tragic, no matter what your age is or what day it is. Secondly, I watched both of these families handle their tragedies with such dignity, grace and strength that it inspires me daily to try and be a better person. Lastly, I had tremendous pride in watching the assigned detectives and their peers work relentlessly together as a cohesive team to solve both of the cases.

Detective Barling has responded to some of our questions and now he'll answer yours. Post them below and he'll be online as of 2pm ET | 7pm BST.

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