The Change.org petition calls for a "formal internal investigation" into how the North Port Police Department in Sarasota County handled Laundrie's case.
Laundrie, age 23, was the only person of interest authorities named in the death of his fiancée, 22-year-old Gabby Petito, both of whom grew up in Blue Point in Suffolk County.
Petito went missing during a cross-country road trip she was taking with Laundrie in late August, and her remains were found by law enforcement in a Wyoming national park on Sunday, Sept. 19.
The Teton County coroner later announced that her death was caused by strangulation.
Laundrie was reported missing by his parents on Friday, Sept. 17, and his remains were discovered by law enforcement in a Florida nature reserve on Wednesday, Oct. 20.
His cause of death has not been announced yet.
"The North Port Police Department has been incompetent in their handling of both Gabby Petito's missing persons case as well as the Brian Laundrie's missing person case," the creator of the petition wrote. "Millions of taxpayers money was spent on this investigation over a month's time with little to no results."
Northport Police spokesperson Joshua Taylor stated in late October that shortly before Laundrie's parents reported that they hadn't seen their son in days, police had mistakenly believed they had seen him at his parents' Florida home.
They later realized they had mistaken his mother for him.
Taylor said aside from causing confusion the mistake "... likely changed nothing. There is a very good possibility that Brian was already deceased."
As of Monday, Nov. 8, the petition has 3,670 signatures, with a goal of reaching 5,000.
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