By Nate Raymond

NEW YORK (Reuters) - A former Long Island banana importer on Tuesday won the reversal of his conviction for assaulting his girlfriend, a decision his lawyer said could impact lengthy federal prison sentences he is serving in two other cases.

The Appellate Division, First Department in Manhattan ruled that a trial judge overseeing the case of Thomas Hoey, 48, improperly met with lawyers in the case outside his presence regarding the admissibility of evidence at trial.

The ruling marked a victory Hoey, the owner of the defunct Long Island Banana Corp. He is serving consecutive federal sentences of 12-1/2 years for a cocaine distribution scheme and 5-1/2 years for stealing from his employees' retirement plan.

Tuesday's ruling stemmed from his May 2014 conviction of third-degree assault and tampering with evidence in the 2012 beating of his girlfriend on Manhattan's Upper East Side, for which he was sentenced to 16 months to four years in prison.

James Kousouros, his lawyer, said in light of the ruling, Hoey would seek to be resentenced in the federal cases, where the state conviction was factored in under federal sentencing guidelines as part of his prior criminal history.

"There could be a relatively significant swing on resentencing," he said.

It was unclear if prosecutors would seek to retry Hoey in the assault case. A spokeswoman for Manhattan District Attorney Cyrus Vance declined to comment.

In March, Hoey was found guilty in federal court on charges that he stole $763,000 from his company's employee benefit plan from 2009 to 2012 by embezzling almost all of its assets and depositing the funds in corporate accounts.

He used the money to pay for company expenses, awarding himself generous raises while spending hundreds of thousands of dollars on corporate credit cards for personal travel and entertainment, prosecutors said.

Prosecutors said Hoey took trips to Britain, Spain, Mexico and Aruba, spent large sums on fine dining and concerts, and stayed in luxury hotels in Manhattan and Long Island despite having residences in both places.

Hoey's April 2015 drug-related sentence came after he pleaded guilty to charges that he conspired to distribute cocaine, including to Kimberly Calo, who died from taking the drug after joining him and another woman in a sex party.

(Reporting by Nate Raymond; Editing by Sandra Maler)