Former alderman and powerbroker Eddie Vrdolyak argued last year that the federal case hanging over him should be thrown out because witnesses who would have testified in his favor are no longer in a position to do so.

Vrdolyak’s lawyers said that one has since passed away and others are in various states of “mental degeneration.”

But in a Monday night filing, federal prosecutors argued that Vrdolyak’s camp has not come close to meeting the evidentiary burden to get the case tossed.

“The defendant must specify exactly what the testimony of the absent witness would have been, and that the absence of this testimony substantially prejudiced the defendant,” prosecutors wrote. “The defendant must also demonstrate that the witness would have testified, that his testimony would have withstood cross-examination, and that the jury would have found the witness to be credible.”

Vrdolyak is set to go to trial this spring on tax charges related to payments he received from Illinois’ multibillion-dollar settlement negotiated two decades ago with tobacco companies.

He was charged in May 2015 with tax counts related to his handling of some $10 million he and co-defendant Daniel Soso allegedly received for an apparently ambiguous role in negotiating a $9 billion settlement with tobacco companies in the late 1990s.

Prosecutors have said Soso did not report income he received from Vrdolyak related to the tobacco settlement.

Last May, Vrdolyak’s lawyers asked that the case be tossed out because of the lost memories of people who could testify in his favor — including those of former Illinois Attorney General Jim Ryan.

Monday, prosecutors said Vrdolyak’s lawyers have not come close to demonstrating that the possible testimony in question would pass legal muster.

“The defendant now speculates that certain witnesses who are no longer available might have been able to provide evidence favorable to the defense in terms of rebutting this evidence,” prosecutors wrote. “But, as noted above, speculation that witnesses might have offered favorable evidence does not suffice to meet the defendant’s ‘monumental hurdle’ of proving actual and substantial prejudice.”