A former Cal State San Marcos student who rigged a campus election by stealing nearly 750 student passwords to cast votes for himself and friends was sentenced Monday in federal court to a year in prison. It was Matthew Weaver’s decision to try to cover up the largest student identity theft in the university’s 24-year history that seemed to irritate the judge the most. “That’s the phenomenal misjudgment I can’t get around,” said Judge Larry Burns, who rejected Weaver’s request for probation. Burns said the election rigging was a serious offense but “kind of juvenile.” Developing a scheme to deflect blame after he had been caught made it worse. “He’s on fire for this crime, and then he pours gasoline on it to try to cover it up,” the judge said.