Some studies estimate that 20 percent of all drownings are actually homicides and missed by law enforcement.
Getting away with murder is the real concern.
Recently, as the I-Team investigated a series of mysterious drownings of college age men and discovered a common complaint from victim's relatives, forensic experts and some police; that all too often when a dead body is found in water, it is presumed to be an accidental drowning.
"Bodies found in water are treated very differently from bodies found on land, for example there is not a county in this country that would take a body in a field and drag it a couple hundred feet before they put it in a body bag and transport it out. It would never happen," said investigator Andrea Zafares.
Zafares is a professional diver and a death investigator in New York state. Zafares has also trained authorities across Illinois in water recoveries. She believes that at least 20 percent of all drowning cases may actually be homicides.
"What we have been teaching around the world is to treat a body with the exact same standards that you would treat a body on land; that requires training," she said.
In the last year, she's trained a Midwest murder task force, the Illinois Coroner's Association and the Illinois homicide investigators association, where state police Captain Jim Winters invited Zaferes to instruct local investigators.
"The more exposure they have to different fields, the better they will be so when they come across something unusual they are going to know," Winters said. "This doesn't seem right and I may not know the answers but I know the questions who to ask those questions to ask or maybe who to ask those questions to."
"You should really approach every scene, whether it's on land or water as a possible homicide," said Zafares. "Part of the problem is, a detective can go into any scene on land, you know, a death investigator, we can go in any scene on land but in the water it's different."
"The diagnoses of drowning depends on the body being found in water and you have no other cause of death," said Dr. Stephen Cina.
Dr. Cina is the new medical examiner in Cook County, which last year handled more than 50 drowning cases.
"Trace evidence can be more of a challenge to recover since the body is washed and has been in a body of water for let's say a week buffeted around by various currents, subtle trace evidence may be lost from the clothing or from the body," Dr. Cina said. "We can still do a complete autopsy in these cases to look for trauma so I don't think we are missing trauma on our cases so it's more challenging."
Last Month, the I-Team looked into dozens of eerily similar cases of college-age men, around the country, disappearing and then found dead in rivers, lakes and streams.
"What we've discovered in all these investigations while looking at the autopsies," said former DEA agent Jerry Snyder. "The body is immediately removed from the water."
Snyder runs, Find Me, a non-for-profit group consisting of criminal investigators from across the country who help with missing people searches and solve crimes. While studying more than 200 of these suspicious drownings, he says there was a disturbing trend.
"By dragging the body or by putting the body in a boat prior to examining it and taking hundreds of photographs as you may be losing evidence as you are taking the body from the crime scene all the way to the shore," Snyder said.
Snyder and other experts are concerned that a large percentage of potential homicidal drownings are not well investigated, or investigated at all, and that police, dive teams and other emergency responders need better training.
The Chicago Police Marine Unit is made up of trained state-certified first responders. It patrols 28 square miles of Lake Michigan shoreline and 27 miles of river, and assists surrounding towns.
When a body has been submerged for an extended amount of time, they say a water evidence team records the location with photographs, the victim is secured from the water and when possible, the body is brought to shore for further investigation by CPD detectives and the medical examiner.
When there is a deadly fire, trained arson detectives are called in. After motor vehicle fatalities, highways death specialists work the scene. The position of water investigator doesn't exist in law enforcement and some experts think it should.
The biggest mistake that police departments make according to researchers is assuming that a dead body in water is just an accidental drowning.