A Newfoundland and Labrador man facing a second-degree murder charge in the death of his infant son has seen the charges withdrawn because a key piece of evidence - the baby's brain – can no longer be found.

Thomas Michel of Sheshatshiu First Nation was charged in November 2013 with second-degree murder in the death of his son, Matthew Rich.

The prosecution team had planned to call experts in forensic pathology and neuropathology to testify as witnesses in the case, the province’s justice department said in a news release.

The experts required access to the baby's brain so they could examine it and provide opinions for the prosecution. But the Chief Medical Examiner's office could not locate the brain of the infant.

They say it appears that the “specimen may have been inadvertently disposed.”

Without the brain evidence, the province’s Public Prosecutions office said “there was no longer a reasonable likelihood of conviction.” As such, the decision was made to withdraw the second-degree murder charge.

“This was not an easy decision for Public Prosecutions to make and was only made after lengthy consultations with the expert witnesses,” the justice department said in its statement.

“…The Public Prosecutions Division of the Department of Justice and Public Safety expresses its sincerest condolences to the family of Matthew Rich.”

Crown prosecutor Elaine Reid said the department learned that the evidence had gone missing “some time ago,” but doesn’t know how it happened.

The Office of the Chief Medical Examiner will now review its policies and decide if it wants to investigate the matter more thoroughly, she told CTVNews.ca.

“It is concerning when evidence does go missing, yes,” Reid told NTV in a separate interview Thursday. “We certainly want to have access to everything that we should and possibly could have access to…and it is concerning as to what happened.”