Disgraced former Assembly Speaker Sheldon Silver will get to remain free on bail while his lawyers try to reverse the longtime powerbroker’s conviction last year on corruption charges, a Manhattan federal judge said on Thursday.

U.S. District Judge Valerie Caproni’s ruling indefinitely postpones Silver’s scheduled Aug. 31 surrender to begin a 12-year prison term, a delay likely to last months as the 2nd U.S. Circuit Court of Appeals decides if a June U.S. Supreme Court decision narrowing federal corruption laws requires a new trial for Silver.

Caproni said that Silver’s behavior would undoubtedly qualify for conviction even under the new, narrower standard for an “official act” that can be part of a corrupt scheme, but jury instructions in his case left open the possibility that jurors might also have convicted for an act that no longer qualifies.

“It is conceivable that a rational jury would not have convicted if it had received complete instructions on… what constitutes an official act,” Caproni wrote, calling it a “close question” and saying any errors in her instructions may have been “harmless.”

Silver, 72, was convicted of doing favors for an asbestos doctor and real estate developers who gave legal work to Silver-affiliated law firms. In a similar decision last month, another judge let former state Senate leader Dean Skelos remain free while he appeals his corruption conviction.

Together, the rulings leave the two singular achievements of Manhattan U.S. Attorney Preet Bharara’s anti-corruption campaign in limbo and mean his most prominent targets will likely remain free into next year. Briefs have not been filed and oral arguments on their appeals have not yet been scheduled.

advertisement | advertise on newsday

The June Supreme Court ruling, in a case that overturned the conviction of ex-Virginia Gov. Robert McDonnell, said that a corrupt quid-pro-quo arrangement involving a public official had to include an “official act” that involved a formal exercise of governmental power.

The alleged favors Silver did, Caproni said, ranged from acts that would qualify, such as arranging state grants, to acts that probably wouldn’t, such as holding a meeting and arranging an internship, and the jury didn’t specify which it thought were part of the corrupt scheme.

In addition to delaying Silver’s imprisonment, Caproni also largely stayed the $1.75 million fine and $5.3 million forfeiture she ordered, but did rule that Silver cannot encumber any assets during his appeal, and must start paying $5,846 per month toward his fine.

Silver lawyers Joel Cohen and Steve Molo said in a statement, “We are grateful that the trial judge agreed there is now a substantial legal question about the conviction. We look forward to vigorously pursuing Mr. Silver’s appeal.”

A spokesman for Bharara had no comment.