Middlesex County Sheriff John P. McGonigle, who presided over Harvard Commencement from 1985 to 1993, was convicted Wednesday on six charges of tax evasion.
McGonigle escaped four more serious counts of extortion, however, when one juror held out against further conviction.
The county suspended McGonigle last year after allegations that he took payments from two deputies in exchange for securing their jobs at a process-serving office.
The Sheriff of Middlesex County, riding on a white horse, has traditionally led Commencement to order each June.
That custorn ended last spring when McGonigle, then already suspended and under investigation, failed to arrive as scheduled at the 1994 Commencement.
After the conviction, Deputy U.S. Attorney Karen Green said the verdict "sends an unequivocal message that if you abuse the public trust for personal gain, you do so at your peril."
But defense attorney Jack Zalkind labeled the tax evasion convictions "technical" and announced his intentions to appeal after the trial.
"This is not the last day in court for John McGonigle," Zalkind said.
Prosecutors plan to retry McGonigle on the deadlocked charges of conspiracy, extortion and racketeering in a trial set for December 19.
In his testimony, McGonigle said he accepted $21,000 from deputies Richard Parella and Robert Kucharzyk, but maintained that the funds were voluntary contributions to his political campaigns.
According to state law, McGonigle will be officially dismissed upon sentencing on January 18.
He now faces up to five years of imprisonment and a $250,000 fine for the one count of conspiracy to defraud the United States. On the five other counts the maximum sentence is four years and $250,000.