By JOSEPH DE AVILA

Connecticut is weighing whether to join a growing number of states that have required universities to adopt policies for sexual interactions known as affirmative-consent.

A proposal before state legislators would create a so-called “yes-means-yes” standard that would be used when investigating sexual-assault complaints.

The push comes as an alleged sexual-misconduct case has shaken up Yale University, in New Haven, with the captain of the men’s basketball team expelled after a campus committee ruled he had violated the school’s policies on sexual conduct.

There is no state law in Connecticut that defines consent in a college setting, said state Sen. Mae Flexer, a Democrat, and co-sponsor of the legislation. “I think this is important so that every college student in Connecticut has the same expectation for safety,” she said.

New York passed an affirmative-consent law in 2015. California and Illinois also have similar laws.

A similar bill passed Connecticut’s state Senate last year 34-1 with bipartisan support. The state House of Representatives never called the bill for a vote. This year’s version passed the Legislature’s Higher Education and Employment Advancement Committee on March 3 by a 14-3 vote.

Republican state Rep. Tim LeGeyt voted against the bill in the committee because, he said, the definition of affirmative consent was too vague and should be refined. “I just think it’s fraught with potential misunderstanding,” Mr. LeGeyt said. “These kinds of misunderstanding could cost someone their college career.”

The affirmative-consent policy would define consent as “an active, clear and voluntary agreement by a person to engage in sexual activity with another person that is sustained throughout the sexual activity and may be revoked at any time by any such person.”

Supporters of the proposed law say it would give victims more safeguards compared with a so-called no-means-no standard.

“That is a completely inappropriate cultural standard,” said Carolyn Treiss, executive director of the Permanent Commission on the Status of Women, a state commission. “We should be operating under a presumption that no one has a right to anyone else’s body unless that person says yes.”

Helen Price, a sophomore at Yale and co-founder of Unite Against Sexual Assault Yale, said setting a statewide standard for all schools would be a positive change. “It’s promoting communication between partners, that people will participate in not only sexual encounters but will be enthusiastic and engaged,” she said.

At Yale, senior and basketball player Jack Montague was expelled in February for alleged sexual misconduct with a woman who is now a junior at the university. Mr. Montague’s attorney this week called the expulsion wrong. Yale has said it doesn’t comment on specific cases of student discipline.

Most Connecticut colleges and universities already have some form of an affirmative-consent policy. The University of Connecticut defines consent as an “understandable exchange of affirmative words or actions indicating willingness to participate in mutually agreed upon sexual activity.”

Wesleyan University defines it as “when all parties agree to engage in sexual activity.” Yale defines it as a “positive, unambiguous, and voluntary agreement to engage in specific sexual activity throughout a sexual encounter.”

UConn implemented its affirmative-consent policy in 2002, said Elizabeth Conklin, Title IX coordinator for UConn. All incoming undergraduate students receive in- person training to discuss the school’s affirmative consent policy during the summer before they begin their first year, she said. There are follow-up training sessions as well. Ms. Conklin said it seems that UConn’s current policies would comply with the proposed affirmative-consent law if it passed.

Critics say the proposed affirmative-consent law would violate the constitutional rights to the presumption of innocence for the person being accused of sexual assault.

“You are trampling on the rights of the defendants in this situation,” said Cynara Stites, a retired University of Connecticut clinical-social worker. She counseled students who had been sexually assaulted on campus, she said.

William O’Sullivan, an attorney from Rocky Hill, Conn., said the state standard used by campuses to determine whether a sexual assault occurred is also problematic.

For handling sexual-assault investigations, Connecticut law requires schools to use the standard of preponderance of the evidence, which is used in most civil cases. That means schools must determine whether the evidence suggests that it is more likely than not that an assault occurred. That differs from criminal court where the standard is beyond a reasonable doubt.

Mr. O’Sullivan said using that standard in such cases violates the student’s due-process rights.

Supporters of the legislation cite the U.S. Department of Education’s Office for Civil Rights, which requires using the standard of preponderance of the evidence for sexual-assault investigations for colleges and universities.

Advocates also say that under the proposed affirmative-consent law, it would still be the burden of the university or college to prove whether it was more likely than not that an assault occurred, and the burden wouldn’t be on those who are accused to prove their innocence.

The new policy would build on a 2014 law that required schools to adopt and disclose their sexual assault policies and to give annual sexual-assault awareness campaigns.

—Zolan Kanno-Youngs contributed to this article.

Write to Joseph De Avila at joseph.deavila@wsj.com

Original Article