WASHINGTON (CN) – Admitted Russian agent Maria Butina claims a declaration from a former FBI official wrongfully accuses her of espionage activity that she was never charged with.

Maria Butina. (Photo via William G. Truesdale Adult Detention Center)

Penned by Robert Anderson Jr., the one-time assistant director of the FBI’s counterintelligence division, Butina said in a filing Tuesday the declaration would transform her sentencing hearing “into a separate trial on unreliable claims with lower burdens of proof.”

“The Anderson declaration raises a wholly new theory of espionage activity that was never charged, never cleared by a grand jury, never disclosed, and never even raised directly with Maria during her 50-plus hours of interviews,” Butina’s response states.

The government submitted the declaration late Friday along with its sentencing memo.

In his declaration, Anderson characterized Butina’s activities in the United States as “part of a deliberate intelligence operation by the Russian Federation.”

The declaration says Russia sought to obtain valuable intelligence information from the operation in which Butina was involved.

After reviewing the material Butina gave her handler, Alexander Torshin, Anderson assessed that it will help Russia identify and recruit vulnerable Americans “for years to come.”

Butina has spent the last nine months in jail following her arrest. She pleaded guilty in December to conspiring to act as a foreign agent, and admitted to working with Torshin to infiltrate the National Rifle Association to create a backchannel of communication between U.S. political figures and Russia.

Anderson said had Butina been successful, Russia could have bypassed formal diplomatic channels, won concessions and exerted influence in the United States.

On Sunday, Butina’s attorney Alfred Carry blasted the government for rolling out its new theory “in the metaphorical bottom of the ninth inning,” and failing to provide evidence to back it up.

The McGlinchey Stafford attorney thus asked the court to bar the declaration rather than allow Anderson to testify at Butina’s sentencing hearing on Friday.

On Tuesday, Carry said finding an intelligence expert to rebut Anderson’s declaration could take months, and that effort would require additional discovery.

He also called into question the government’s good faith. His client pleaded guilty after the government induced her “with aspirational promises of a cooperative sentencing hearing.”

Such promises, Carry added, “have not borne out.”

Tuesday’s filing came in response to a minute order Monday asking Butina’s attorneys to state how long they would need to respond to the declaration. Carry said no adjournment would be sufficient within the context of the case.

In its own response filed late Tuesday afternoon, the government said it gave Butina ample notice of the declaration.

“Neither the Constitution nor any rules required the government to provide the defense with notice of the expert testimony prior to sentencing,” the opposition brief states.

Erik Kenerson with the U.S. Attorney’s Office for the District of Columbia said in the filing that the government does not object to giving Butina’s defense team more time to respond to the Anderson declaration.

The government asked the court last Friday to sentence Butina to 18 months, shaving only six months off the 24-month sentence they said would be appropriate without her cooperation.

The government based its request on the potential national security harm that could have resulted from Butina’s actions.

Her attorneys meanwhile have asked the court to release her with time served.

Butina is scheduled to be sentenced on Friday at 10 a.m.

The parties did not immediately respond to a request for comment.