An influential group of law professors has once again declined to recommend that state governments enact policies favoring accusers in sexual assault cases, changes that already have been adopted by many colleges and universities.

A proposal that would newly criminalize many sexual activities as assault was offered by two New York University professors at The American Law Institute’s annual conference in Washington last week.

This is the third year in a row that law professors Erin Murphy and Stephen Schulhofer introduced their proposal. Once again, they faced strong backlash as more than 100 opponents wrote a letter detailing their concerns, with several introducing motions to alter the language of the draft.

Little known outside the legal profession, ALI is a professional association of judges, lawyers and legal scholars that has shaped many laws in this country since it was founded in 1923. Its 1962 Model Penal Code, for example, was adopted in part by nearly two-thirds of the states and almost word-for-word in New Jersey, New York and Oregon. If the ALI endorsed a new approach to sexual assault laws, it would almost certainly serve as a model for state legislatures across the country.

The ALI’s debates illuminate the difficulty of translating aspects of sexual behavior into legal standards. One of the primary disputes involves Murphy and Schulhofer’s efforts to include an “affirmative consent” standard in sexual assault law. Sometimes called “yes means yes,” this standard requires prior permission before each and every interaction during a sexual encounter. Critics say such policies either turn sex into a question-and-answer session or make nearly all sexual encounters sexual assault by default.

Nevertheless, affirmative consent has been adopted by nearly 2,000 colleges and universities. California, Illinois and New York have passed laws mandating the policy be used at all state colleges, while similar legislation is pending in another 22 states, according to a map maintained by the website AffirmativeConsent.com.

Some schools have gone a step further, decreeing that affirmative consent be “enthusiastic” or even “sober,” “imaginative” and “creative.”

At ALI’s 2016 conference, a vigorous debate was held over the definition of consent, with much of the affirmative standard being removed. At the 2017 conference, Murphy and Schulhofer circulated a document titled “Current State of the Law – Consent-Only Offenses,” which explained that “[a]t least 32 American jurisdictions punish penetration in the absence of consent, without requiring proof of additional elements such as force, resistance or expressed unwillingness.”

Murphy and Schulhofer’s continued references to affirmative consent have kept opponents unnerved. In an attempt to stall the draft from ever being approved by the broader ALI membership, those opponents introduced three proposed changes to the draft, of which only one was adopted. Each involved minor changes to the definitions of sexual penetration, oral sex and forcible rape. Despite the failure of two of their proposed changes, the opposition group was able to delay formal acceptance of the draft for at least another year.

Nonetheless, K.C. Johnson, a history professor and co-author of “The Campus Rape Frenzy,” told Real Clear Investigations that what happened at ALI this year was not a clear rejection of bringing campus policies to the general population.

“[I]t features something extraordinary – important players on the legal left, for the first time in decades, demanding changes in the criminal code that will dramatically increase incarceration rates,” Johnson said in an email. “And, it’s clear, ALI advocates of overcriminalization won’t take no for an answer – despite their proposals being rejected at previous stages, they keep coming back, evidently hoping to wear down defenders of civil liberties (or, for that matter, common sense) within the ALI.”

The draft will now go back to Murphy and Schulhofer for further revisions, and additional provisions will be discussed at the next annual meeting.

This article originally appeared on RealClear Investigations.