According to multiple sources, free agent quarterback Colin Kaepernick has filed a grievance against the NFL for collusion. In March, I wrote a legal analysis of this scenario occurring and explained how it would work for Kaepernick and the NFL. The March article details the relevant procedures at play and how they are governed by the collective bargaining agreement.

Here’s an update, and 16 key points to stress.

1. Collusion requires actual cooperation between teams (or cooperation between a team or teams and the league)

Here’s a scenario that has probably played out in recent months: Officials on one NFL team meet to discuss the team’s need for a quarterback. Kaepernick is one player they discuss. The officials then decide, without the involvement of any other team, to not sign Colin Kaepernick. Instead, the team signs a quarterback who, by objective metrics, isn’t as good as Kaepernick. These officials even admit to taking such an approach because they believe that Kaepernick would be a distraction. They also openly disagree with his political views and are offended by his kneeling during the national anthem.

Sounds suspicious, right? It’s not, at least not for purposes of collusion.

The scenario I just described is not collusion because it involves only one team. To be sure, those officials might regret not signing the “better” player. That’s not the point. It is lawful for one team to not want Kaepernick on grounds that team officials don’t like him. Along those lines, no NFL team is legally obligated to sign Kaepernick.

For Kaepernick to prove collusion, he would need to show that two or more teams, or the league office and at least one team, conspired in some way to deny him an opportunity to play in the NFL.

2. Kaepernick needs evidence of collusion

Kaepernick needs more than mere supposition or belief that he has been victimized by a conspiracy. Perhaps he has an email, text, social media message, video, audio recording, hand-written note or sworn testimony from a witness. Maybe his agents, Jeffrey Nalley and Sean Kiernan, are in possession of such evidence. Regardless, the evidence must clearly show that two or more teams, or the NFL and a team or teams, conspired to deny Kaepernick of an opportunity to play in the NFL.

So where might Kaepernick have uncovered evidence that he believes proves collusion? We know that if it occurred, it must have been within the last 90 days, as under Article 17 of the CBA a player has that long to file a grievance. Otherwise we are left to speculate.

One possibility: Given the public uproar over players engaging in a form of protest during the national anthem, could officials on different teams have exchanged emails about the topic and, in doing so, pin the blame on Kaepernick? Sure. After all, Kaepernick began the controversy last season.

Yet even if Kaepernick is in possession of those kinds of emails, they may not prove collusion. He would need to show that he has been deprived of a collectively bargained right—namely, the right to sign with a team. Emails from officials on different teams merely criticizing him might not rise to the necessary level.

3. The fact that Kaepernick is probably “better” than some quarterbacks currently on NFL rosters does not prove collusion

In recent weeks, various media commentators have opined that quarterbacks inferior to Kaepernick are on NFL rosters. Some of those quarterbacks are even starting NFL games.

Collusion?

No. As mentioned above, some teams might not want Kaepernick simply because they don’t like him. They might prefer an inferior quarterback as the backup since he would not attract controversy or draw attention away from the starting quarterback, or he better fits the team’s offensive scheme. Whether such an approach is in the best interests of a team can be debated. But for purposes of collusion analysis, Kaepernick’s superior talent compared to some NFL quarterbacks doesn’t—by itself—prove anything.

4. Kaepernick proving that owners or team officials are racially insensitive would not prove collusion

If Kaepernick can prove he has been the victim of racial discrimination by NFL owners, such discrimination would not necessarily advance a collusion grievance. As noted above, Kaepernick would still need to show that teams conspired.

That said, other legal claims might become available for Kaepernick in such a scenario. For instance, he could file a charge with the Equal Employment Opportunity Commission, which is entrusted with guaranteeing that employees are not subject to illegal forms of discrimination.

Kaepernick and the NFLPA could also pursue potential remedies available through the National Labor Relations Board. To that end, Kaepernick might insist that the NFL is in violation of Section 7 of the National Labor Relations Act by denying him a chance to engage in a concerted activity—anthem protest. Such protest, it could be argued, would advance the union’s bargaining interests.

5. Kaepernick proving that owners or team officials are “colluding” with President Trump would not prove collusion

On several occasions, President Donald Trump has leveled sharp criticism against Kaepernick for kneeling during the national anthem. Trump has even urged NFL owners to cut players who do not stand during the national anthem. By implication, Trump has signaled that he’d prefer teams not sign free agents who would kneel during the anthem. I have written about the legal implications of Trump’s NFL-related comments here and here.

Could the President of the United States be a key person in a collusion grievance brought by Kaepernick?

Probably not.

An NFL owner agreeing with Trump, or even communicating with Trump about Kaepernick, would not constitute collusion under the CBA. Trump is an external actor for purposes of collusion analysis. That is, he is not a party to the CBA and is therefore not governed by it.

If, however, multiple NFL owners have communicated through Trump about Kaepernick, perhaps there would be evidence of collusion. But Trump would not be the collusive party—it would be the owners.

At least in theory, there may be other legal recourses for Kaepernick against Trump. One federal criminal statute, 18 U.S. Code § 227, has attracted some attention because it prohibits the President from “wrongfully influencing a private entity’s employment decisions.” If the President is charged and convicted of violating this statute, he would be disqualified from office and face up to 15 years in prison.

This statute, however, is limited in crucial ways that make it virtually inapplicable to any real-world situation. One key way: To gain a conviction, a prosecutor would need to prove beyond a reasonable doubt that Trump acted “with the intent to influence, solely on the basis of partisan political affiliation” (emphasis added). Logically, it seems almost impossible to imagine a prosecutor proving that Trump directed NFL owners to not sign Kaepernick—who reportedly didn’t vote in the 2016 election—solely because of partisan political affiliation and no other reason whatsoever.

6. Kaepernick opting out of his San Francisco 49ers contract doesn’t disprove collusion

Much has been written about the fact that Kaepernick opted out of his contract with the 49ers in March. He was scheduled to to make $16.9 million in salary and bonuses in 2017, though the 49ers would not be on the hook for that if they cut him, and various media reports suggest Kaepernick opted out after learning the 49ers were going to do so.

Some have reasoned that because Kaepernick opted out of his contract, he somehow waived any potential collusion claim.

That is incorrect. In fact, there is no connection between the two. If teams conspired against Kaepernick in recent months, he would still be a victim of collusion. His opting out of his contract with the 49ers in March would be irrelevant.

7. Kaepernick turning down free-agent offers wouldn’t disprove collusion

Some have speculated that Kaepernick might have told teams, or at least implied to them, that he wants to start. It’s also possible that Kaepernick has turned down overtures—perhaps even offers—from teams that want to sign him.

None of that would prevent Kaepernick from proving collusion. Why? Because an alleged conspiracy might have involved other teams and their officials. If two teams colluded against Kaepernick, and the 30 other teams did not collude, Kaepernick would still have been victimized by collusion.

8. The arbitrator will be neutral for Kaepernick’s grievance

Kaepernick’s grievance falls under Article 17 of the CBA. It dictates that a “system arbitrator” will preside over the proceedings. Such an arbitrator is neutral and selected by both the NFL and the NFLPA. This is, of course, a very different system of dispute resolution than that experienced by NFL players who challenge player conduct suspensions under Article 46 of the CBA. Under Article 46, NFL commissioner Roger Goodell is the presiding officer (arbitrator) unless he delegates that responsibility to someone of his choosing. Kaepernick, in contrast, will have an impartial person review his claim.

9. Kaepernick must satisfy the “clear preponderance of the evidence” burden

The system arbitrator will not decide the grievance based on whether Kaepernick has “probably” proven the case. Kaepernick must be somewhat more convincing: He must persuade the arbitrator through a “clear preponderance of the evidence” that collusion occurred and caused him economic injury. The word “clear” in conjunction with “preponderance of the evidence” is noteworthy. Legal commentators who have studied this burden find that the evidence must be compelling in order for the burden to be met.

10. An arbitration hearing isn’t as worrisome to the NFL as would be a trial

The hearing for Kaepernick’s grievance will be a private arbitration hearing—not a public trial. Although the federal rules of evidence will apply, NFL arbitration does not involve nearly the same degree of pretrial discovery as found in a trial. No subpoenas or warrants will be available in such a forum, and witnesses cannot be compelled to testify upon threat of being jailed. These dynamics could limit the ability of Kaepernick to force the NFL to answer to his claims or theories.

11. If Kaepernick wins, he could receive many millions of dollars

If Kaepernick can prove collusion, he stands to receive a sizable amount of money. His damages would be trebled: hypothetically, if Kaepernick proves that collusion cost him $10 million, he would be awarded $30 million in damages.

This is because Kaepernick would be awarded two types of damages. The first would include compensatory damages for the money he lost due to collusion. Under the penalty scheme for collusion, Kaepernick would also receive non-compensatory (or punitive) damages of twice the value of his compensatory damages (thrice if the team is a repeat offender, though no team is likely in such a category).

How could an arbitrator be sure as to the appropriate amount of compensatory damages for Kaepernick? It would clearly be a difficult analysis. The arbitrator would have to envision a world that never occurred and then surmise what Kaepernick, at age 29, would have earned in it.

One way to help the arbitrator would be through “comparables”—salaries of other free-agent quarterbacks who signed with NFL teams in 2017. To that end, it is worth noting that 27-year-old Mike Glennon signed a three-year deal with the Chicago Bears for $45 million, 31-year-old Brian Hoyer signed a two-year deal with the 49ers for $12 million, 34-year-old Jay Cutler signed a one-year deal with the Miami Dolphins for $10 million, and 37-year-old Josh McCown signed a one-year deal with the New York Jets for $6 million. As I wrote earlier this year, football experts could argue that Kaepernick, who threw 16 touchdowns against four interceptions in 2016, was superior to those players: He enjoyed a higher QB rating (90.7) than McCown (72.3) in 2016 and a higher career QB rating than that of Hoyer this year (74.1).

12. If Kaepernick loses his grievance, he could appeal to federal court—but he would probably lose again

Just like other players who lose NFL arbitrations, Kaepernick would be able to sue the NFL (and any colluding teams) in a U.S. District Court. In doing so, he would petition a federal judge to vacate the arbitration decision.

As evidenced by recent lawsuits that ultimately failed, players have not experienced a great deal of success in suing over arbitration awards. This is in part due to the high level of deference judges owe arbitrators under federal law—even when, as stipulated by Article 46 of the CBA, the arbitrator is the NFL commissioner or a similarly non-neutral designate. Challenging an Article 17 collusion decision might prove even more problematic for Kaepernick given that the arbitrator would be a neutral and presumably more credible figure.

13. The NFL has experienced limited interaction with collusion claims

Only once in recent years has the NFL battled a collusion claim. In 2011, the NFLPA claimed that teams conspired to cap player salaries during the uncapped 2010 season. The matter was ultimately heard by a federal appeals court, which was tasked with resolving several matters related to the collective bargaining relationship between the NFL and NFLPA. The court did not find evidence of fraud.

14. Baseball has a longer history of collusion

On several occasions Major League Baseball players have proven that the league and its owners conspired to unlawfully restrict player salaries. In the 1980s, owners were shown to have reached a “gentleman’s agreement” to not bid for each other teams’ free agents—a clear violation of baseball’s collective bargaining agreement. Players learned of such plots through their agents, who were able to gain statements from baseball officials that in turn proved collusion.

Not all collusion matters against baseball have been resolved favorably for the players. In 2015, an arbitrator rejected a collusion grievance brought by Barry Bonds on grounds that Bonds—who offered to sign with any team for the league minimum—lacked evidence of collusion.

15. Kaepernick has retained a well-known attorney for his grievance

Bleacher Report’s Mike Freeman reports that Kaepernick has retained Mark Geragos, a high-profile attorney, to litigate the grievance. Although perhaps best known for representing such Hollywood stars as Michael Jackson and Winona Ryder, Geragos also has sports law expertise. He represented NASCAR driver Jeremy Mayfield in his attempt to defeat a drug suspension.

16. If Kaepernick is signed by an NFL team, he could—but not must—drop his grievance

With quarterback injuries and underperformance, calls for teams to sign Kaepernick continuously surface. The latest example concerns the Green Bay Packers. In Sunday’s Packers-Minnesota Vikings game, Aaron Rodgers suffered a broken right collarbone. The injury could cause Rodgers to miss the entire season. Backup quarterback Brett Hundley took over for Rodgers in the Vikings game. Hundley struggled at times, throwing three interceptions and completing only 18 of 33 passes. While it’s too early to draw any conclusions on Hundley, who until Sunday had only thrown 10 passes in the regular season, the Packers will be on the market for another quarterback to join Hundley. Perhaps they will consider Kaepernick.

If Kaepernick signs with the Packers or another team, he might decide to drop the grievance. His focus would presumably be on adjusting to a new playbook and helping his team win. A grievance procedure might become a distraction.

Kaepernick, however, would not be obligated to drop the grievance if he signs with a team. He could still attempt to prove that he was victimized by collusion.

Michael McCann is SI’s legal analyst. He is also an attorney and the Associate Dean for Academic Affairs at the University of New Hampshire School of Law, and co-author with Ed O’Bannon of the forthcoming book Court Justice: The Inside Story of My Battle Against the NCAA and My Life in Basketball.

This story originally appeared on SI.com.

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