Facing sentencing Wednesday on federal tax fraud charges, former Traffic Court Judge Michael J. Sullivan offered an unusual argument to the court: Come on, really?

Yes, the judge had paid most of the staff at his family bar in South Philadelphia under the table in cash, his lawyer said. And yes, he pleaded guilty last year to failing to report $48,089 in payroll taxes over 11 years.

But in a city burdened by violent crime and serious public corruption, defense attorney Henry Hockeimer asked, don't federal authorities have anything better to investigate than a neighborhood bar where employees never made more than $30 to $40 a shift?

"I don't see how this is a prosecutorial priority," Hockeimer said. Referring to his own past experience as a Justice Department lawyer, he added: "We just didn't do this kind of stuff. We didn't go after people in misdemeanor tax cases."

He argued that federal sentencing guidelines that called for a sentence of 10 to 12 months overstated the seriousness of the crimes.

"I'm not saying he didn't plead guilty. I'm not saying he didn't admit responsibility," Hockeimer said. "But should he go to jail for that?"

U.S. District Judge Eduardo Robreno was not so dismissive, sentencing Sullivan, a former Democratic ward leader and union operating engineer, to 10 months in prison.

"He was a public official, and he was cheating on his taxes," the judge said. "I recognize it's a relatively small amount of money, but under the circumstances it's a serious offense."

In Hockeimer's view, the case against his client stemmed from the outcome of an entirely different set of charges - the 2014 conspiracy-and-fraud trial that sent four other former Traffic Court judges to prison for lying about rampant ticket-fixing at the court. Sullivan was the only judge acquitted of all counts.

Within days of that verdict, Hockeimer alleged, prosecutors called him, revealed the looming tax case, and threatened that if Sullivan did not plead guilty, other members of his family also could face charges.

But Assistant U.S. Attorney Paul L. Gray balked Wednesday at any suggestion that his office retaliated by bringing charges for crimes that otherwise would have been ignored.

"Whether it's a small Philly bar where they make maybe $40 a shift or if it's a tonier bar where they make $80, I don't think it makes all that much difference," he said. "We certainly cannot ignore [the cases] that come to our attention - especially when they involve a politician."

FBI agents uncovered the evidence at the heart of Sullivan's tax case in 2011 at his home and his family's bar, the Fireside Tavern, near Marshall Street and Oregon Avenue, during raids tied to the Traffic Court investigation.

Documents they seized showed that in addition to not paying the bar's payroll taxes, Sullivan bilked the IRS out of an additional $10,000 on his personal income tax forms.

Gray said Wednesday that prosecutors set those papers aside for years while focusing on the Traffic Court corruption case, which culminated in a two-month trial at which prosecutors alleged judges routinely tossed traffic citations for friends, family members, and political allies.

But although the jury in that case agreed that Traffic Court's corruption was endemic, it ultimately decided that the ticket-fixing the government outlined was a judicial ethics problem more than a federal crime.

It acquitted all of the five judges who took their case to trial on the most significant counts against them, while convicting four on lesser charges of lying to federal authorities.

As the only judge who never agreed to talk to FBI agents or testify before the grand jury, Sullivan walked free and was less than charitable while discussing the government's case after the verdict.

"As far as I am concerned, I was indicted for doing my job," he told reporters.

In court Wednesday, despite his lawyer's claims of prosecutorial retaliation, Sullivan was more contrite.

"I just want to apologize to the court for putting myself and my family in this situation," he said. "I am going to make sure all the taxes are being paid - probably within 60 days."

jroebuck@phillynews.com

215-854-2608 @jeremyrroebuck