US District Judge Amy Berman Jackson on Thursday struck down Paul Manafort's motion to suppress evidence against him in the Russia investigation.

The evidence in question was obtained from a storage locker in Alexandria, Virginia, that belongs to Manafort's consulting firm, Davis Manafort Partners, Inc.

FBI agents were authorized by a warrant to take various records from the unit, including those related to Manafort's financial and lobbying activities in Ukraine.

Though Jackson's decision on Thursday was not unexpected, it strikes yet another significant blow to Manafort's defense as his legal troubles mount.

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A federal judge in Washington, DC, denied Paul Manafort's motion on Thursday to suppress evidence against him obtained from a storage locker in Alexandria, Virginia, belonging to his consulting firm, Davis Manafort Partners, Inc.

Manafort is the former chairman of President Donald Trump's campaign and a key target in the special counsel Robert Mueller's investigation into Russia's interference in the 2016 presidential election.

Manafort is a defendant in two separate cases from Mueller's office, one in Virginia and another in Washington, DC. He stands charged with over two dozen counts related to tax and bank fraud, obstruction of justice, conspiracy, making false statements, and failure to register as a foreign agent. He has pleaded not guilty to all charges.

According to an earlier court filing, an FBI agent first searched the storage locker in Alexandria on May 26, 2017 after obtaining permission to do so from a "low-level" DMP employee responsible for carrying out administrative functions.

The FBI agent then "observed a number of boxes and a filing cabinet" and "some writing on the sides of some boxes," the document said. The agent returned on May 27 with a search warrant relying on information he had surmised when he visited the storage locker the day before and subsequently seized documents and binders from the property.

Manafort's attorneys argued that the evidence in question should not be used in court because the initial search was conducted without a warrant.

On Thursday, US District Judge Amy Berman Jackson wrote that the initial search was lawful because the FBI got permission to conduct it from a person listed as a lessee for the storage locker. She added that even if the initial search was unlawful, the seizure of the storage locker's contents was lawful because the search warrant the FBI obtained was based on an affidavit that spelled out why investigators believed Manafort was engaging in criminal activity.

The warrant that a federal judge, Theresa Buchanan, issued authorizing the search and seizure of the locker's contents on May 27 permitted investigators to seize any records related to Manafort or his longtime associate, Rick Gates.

They were also allowed to take records related to former Ukrainian President Viktor Yanukovych; the pro-Russia Party of Regions that Yanukovych led; the lobbying firm called the Podesta Group, which shut down earlier this year after facing scrutiny in the Russia probe; a think tank known for pushing Russia-friendly positions called the European Center for a Modern Ukraine; and several offshore companies Manafort is linked to.

Another key pillar of Manafort's lawyers' argument to suppress evidence was that the warrant itself was too broad and amounted to a carte blanche in violation of Manafort's Fourth Amendment right against unreasonable search and seizure.

Jackson on Thursday struck down that argument as well, writing that the warrant specifically instructed FBI agents to look for evidence related to the criminal activity Manafort is alleged to have engaged in according to the affidavit.