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Farmington, Rosemount police are developing sophisticated crime scene teams

Farmington police officer Brianna Dirks uses fluorescent dusting powder to demonstrate how she finds fingerprints. Dirks and three more Farmington officers make up the department's Crime Scene Unit.

They might not have all the impressive gadgets, computer programs or immediate matches you might see on the popular television series CSI or NCIS, but when it comes to crime scene investigations, the police departments in Farmington and Rosemount can still get results.

Local police departments have spent a good deal of time training officers to develop specialized skills that help document a crime scene, run tests and hopefully find the evidence necessary to solve crimes in their own communities.

Both Farmington and Rosemount have had individual officers trained to do evidence collection for the better part of a decade. But it has only been in the past five years or so that the departments have set aside time for training and cultivated groups designated as crime scene units.

The need for specialized units traces back, in part, to a phenomenon known in police circles as "the CSI effect," according to Farmington Police detective sergeant Lee Hollatz.

"That show came out, everybody is into it. Everybody sees that the cops have the fingerprints and the DNA and the evidence. Then when we'd get to a big jury trial, the jury was always looking for that evidence," Hollatz said.

Farmington has had an official Crime Scene Unit since 2008. The unit is headed by officer Brianna Dirks, who works with officers Andrew VanDorn, Cassie Redmond and Gary Tipton. The CSU works closely with FPD's detectives, though both have a very specific role when a crime is reported.

"When detectives were on these cases, the detectives were busy investigating the elements of the crime, the personnel involved, the witnesses and the suspects, victims and bystanders," Hollatz said. "It was very difficult for a detective to go into a crime scene and process and also investigate it at the same time, especially on the bigger cases where those first few hours are very important."

Rosemount's Crime Scene Team was established approximately three years ago, detective John Winters said, though the department has trained individual officers and detectives in crime scene processing for the better part of a decade.

These days, the Rosemount Police Department's CST is made up of Winters; sergeant Henry Cho; officers Krista Erickson, Beth Richtsmeier and Ryan Coughlin; and detective Julie Rauenhorst.

"We've all had some additional training," Winters said. "It's pretty much ongoing training that we do, and now we've started to do our own inter-department training as well."


Training is a big part of becoming a crime scene investigator. In Farmington, Dirks started her training back when the CSU was first established. Over the years, CSU members have attended training sessions around Dakota County, the state, and even a few national sessions.

Training includes photography, DNA collection, fingerprint collection and analysis, among other things. Dirks has done advanced training on chemical processes, alternate light sources and how to do things like lift prints that are several years old.

Often, officers who are part of the crime scene investigations are also the ones who teach colleagues in their own departments. On Wednesday this week, RPD sergeant Cho hosted a training session on how to treat and collect blood spatter evidence, because Cho had recently attended a training on the matter, Winters said.

"In theory, if we have a crime scene, we prefer to have the (CST) members process the scene, and that's why we have several different officers. They work different shifts, so if there's something going on, we like to have one of the team members go there and take photos and grab the evidence. But any officer can grab evidence and put in a request to process," Winters said.

The same applies in Farmington.

"All of our officers are trained to recognize important pieces of evidence," Dirks said. "Each piece has a way to be identified and handled. Patrol officers know that, but if they get to a crime scene, we will come in even if we're not working to process the scene."


Once evidence is collected, it's brought back to each respective department for processing. Both departments have set aside specific areas in their buildings where the work can be done, but what goes on in that area is kept somewhat confidential.

Processing fingerprints and DNA is a central part of the job. Police have different methods of pulling prints, depending on what surfaces those prints are on, and it's one of the first things they do when processing evidence.

But from there, it gets more advanced.

Dirks said one of her favorite things about investigations is when she's able to find traces of blood or other DNA that helps to put a suspect at the scene of the crime.

"Physical evidence it so important, because people's verbal statements can change, or witnesses could not be creditable, whereas, evidence typically does not lie. As long as you've handled it properly and you've maintained the chain of custody, that's a really sound foundation to build your case on," she said.

Most departments in Minnesota process DNA evidence by sending it to the Minnesota Bureau of Criminal Apprehension. There, DNA is analyzed and stored in a database that helps to track individuals who have committed serious crimes. In some instances, DNA matches can help close old cases, as well.

"We've sent in a lot of evidence and we've gotten some very good results, which is very gratifying," Winters said.

Another option out there is Burnsville's police department, Rosemount chief Eric Werner said. Burnsville has a crime scene vehicle that offers a mobile option to bring in more help and materials for larger crime scenes. Additionally, all of the police departments in Dakota County benefit from the domestic preparedness team, which has members from every department in the county.

"Dakota County agencies have a fantastic working relationship with each other," Werner said. "In regards to investigations you have many evidence collection people. They meet often to communicate about cases, talk about what's going on and so on. Crime is not contained to a community's borders."

Michelle Leonard

Michelle Leonard joined the Woodbury Bulletin staff in November, 2014, after 14 years covering news for the Bulletin's sister publication, the Farmington Rosemount Independent Town Pages.  Michelle earned her Bachelor of Science degree in Mass Communications: News-Editorial from Mankato State University in 1991. She is an active member of the American Legion Auxiliary Clifford Larson Unit 189 of Farmington, and served as the 2014-15 Third District President to the American Legion Auxiliary Department of Minnesota. Michelle is also the volunteer coordinator for the Minnesota Newspaper Museum which is open annually during the Minnesota State Fair. She has earned Minnesota Newspaper Association awards in Investigative Reporting, Local News Coverage, Feature Photography and Column Writing. 

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