Huma said Northwestern seemed to be intentionally misconstruing the facts, and said the school's "subliminal messages" included the suggestion that a "yes" vote could throw their amateur status into question.
"No one is taking about striking," he said. "They are trying to rattle players."
Northwestern did not release the document publicly, but The Associated Press obtained a copy and the school verified its authenticity. Alan K. Cubbage, the school's vice president for university relations, dismissed Huma's suggestion that the school was using scare tactics.
"I would say strongly that Northwestern has conducted an election campaign ... according to the procedures and the rules of the NLRB," he said.
When outgoing Northwestern quarterback Kain Colter announced in January that he would lead the drive to unionize, helped by CAPA and the United Steelworkers, he said nearly all of his fellow teammates were behind him.
Trevor Siemian, who is expected to replace Colter as the starting quarterback, has said he will vote against a union.
"I'll say there's a significant number of guys on the team who feel the same as me," Siemian said this month.
Safety Davion Fleming said his teammates have slowly begun to understand that the issues aren't clear cut.
"When the union talk initially started, it wasn't very clear what was going on," said Fleming, who doesn't support unionization but can't vote because his eligibility is exhausted. "I think they didn't understand the implications."
After weeks of both sides vying for votes, Fleming said he detects a common sentiment among players.
"They just want this to be over — and to focus on football," he said.
AP Sports Writer Jay Cohen contributed to this report.
- BYU football: The Nebraska Cornhuskers in 6...
- Utah's 'big game' against Big Blue has...
- Cougars respect Nebraska, but say they...
- Red and blue recruits: Jaren Hall excited for...
- Flaming spears, furry mascots and drum lines:...
- Morning links: Taysom Hill profiled by ESPN;...
- Dick Harmon: College predictions: Utes to...
- Randy Hollis: Here's how 'Big Five' football...
- Lone Peak's Frank Jackson sees Duke as... 76
- BYU's Davis faces misdemeanor assault,... 69
- BYU football notebook: Team captains... 51
- Michigan to debut its Harbaugh era in... 37
- Utah's 'big game' against Big Blue has... 34
- Take expletives, not religion, out of... 30
- Cougars looking for special season with... 29
- Morning links: Taysom Hill, Chuckie... 28