Federal agents will keep possession of a mysterious bundle of $17,900 in cash found in a backpack by a passenger aboard an Amtrak train at Washington, D.C.’s Union Station, after a months-long court battle over the cash.

A federal judge has ruled two New York City women who made formal claims for the cash were not credible enough to be given possession of the money.

The cash that an Amtrak passenger found when he walked off a train with the wrong backpack will remain in the custody of the Drug Enforcement Agency.

The DEA formally sought possession of the money from the Metropolitan Police Department, which recovered the cash from the good Samaritan that turned it in.

The DEA said there was reason to believe the money was “intended to be furnished by a person in exchange for a controlled substance,” according to court filings.

The saga of the cash began in 2014, when the good Samaritan notified police he had found $17,900 in a backpack that he mistakenly carried off a train.

According to a report from investigators obtained by the News4 I-Team, the man discovered the cash tucked inside the bag. The man, who is referred to in court records only as M.M.A., notified Amtrak police.

According to paperwork filed by federal prosecutors in the U.S. District Court for the District of Columbia, the money was linked to another passenger aboard the train, a man named Peter Rodriguez, who remained on board until the Amtrak train reached New York City. Rodriguez acknowledged being the owner of the bag, but denied carrying money in it, according to court filings.

In the following months, Rodriguez was arrested for selling controlled substances in New York.

Rodriguez’s mother and her domestic partner formally claimed ownership of the money and asked a court to order officials to hand over the cash to them. The women, Angela Rodriguez and Joyce Copeland, argued they had placed the bag of cash in Peter Rodriguez’s bag without notifying him.

Copeland told investigators she had sold a mink coat to raise some of the cash, according to court filings. The couple said they pooled the cash to purchase a car for a planned move from New York to North Carolina.

A federal judge, in an opinion reviewed by the I-Team, dismissed Rodriguez and Copeland’s claims for the cash. The judge said the couple’s story “defies common sense.”

“The claimants allegedly stored thousands of dollars in cash for months on end despite having access to interest-bearing Citibank and JPMorgan Chase accounts," the judge said in his formal opinion.

“Lastly, and most decisively, the Court rejects as outlandish that Claimants would have left a bag containing $17,900 in Peter’s backpack -- or anywhere else in his apartment -- rather than keep it in their protective custody until it could be spent as intended," the ruling also said.

The good Samaritan who reported finding the cash has not been identified.

News4 was not able to reach Rodriguez or Copeland for comment.