The latest happened Monday morning near 46th and Josephine in northeast Denver when a man riding his bike to work was killed.
He's been identified as David Pickett, 50, from Lakewood. Denver Police say they still don't have a vehicle description and are looking for witnesses.
Former police officer and professor of criminal justice at Metropolitan State College of Denver, Joseph Sandoval, says police often have a difficult time finding answers in these kinds of cases.
In fact, it was just a couple days ago when a neighbor's surveillance camera showed a 10-year old boy being hit and miraculously, walking away with only a few scrapes.
Perhaps what remains one of the most talked about unsolved hit and runs is the case of Laurie Gorham when last December, she lost her unborn baby to a hit-and-run driver.
"One would think that someone's conscience would truly bother them!" said Sandoval.
Sandoval says the State takes their decision to leave more seriously.
"Even if someone's injured, and the person does not flee the scene, there may be a felony involved, but judges usually look at that with some leniency," said Sandoval.
Sandoval points to the economy for one of the reasons why people act callous and choose to leave the scene.
"Insurance isn't cheap these days, and it costs a little bit to maintain a driver's license," said Sandoval.
When a driver decides to leave, police lose a crucial piece of the crime scene puzzle. While it used to be the only way to solving that puzzle was when a guilty conscience came clean, he says times may be changing with the use of surveillance and traffic cameras.
"With the explosion of technology these days... it would not be inconceivable that in our lifetime, we would see cameras on every street corner and that it would be increasingly more difficult not to be identified," said Sandoval.
Denver Police say they're still investigating Monday morning's hit and run.
The Denver Office of the Medical Examiner has not yet released the results of the autopsy in that case.
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