Judge Denies Josh Duggar's Motion to Vacate Conviction

Josh Duggar just got shut down in his bid to throw out his conviction after a judge called his excuse for filing his docs too late "not credible."

The "19 Kids and Counting" star filed a motion looking to vacate his conviction for possession of child sexual abuse material, claiming his constitutional rights were violated.

But the judge rejected his bid after finding he filed his appeal too late … according to court docs obtained by People.

The judge said the U.S. Attorney's Office got Josh's appeal last July -- over a month past the deadline -- and the court didn't get a copy until August.

Josh argued that shouldn't matter because of the "prison mailbox rule" … which says motions "deposited in the institution's internal mailing system on or before the last day for filing" are still timely.

But the judge ruled that Josh's testimony about when he mailed the docs was a bit far-fetched, saying … "The Court can grant Mr. Duggar one coincidence. Perhaps even two or three odd happenstances. But Mr. Duggar is asking the Court to believe something akin to a magic bullet theory—a sequential chain of events that defies common sense."

The judge said as a whole "this chain of events—where Murphy's law was lurking at every turn—is simply not credible."