Can Union Enforce a Fine Against Members Who Cross a Legal Picket Line?

The Ontario Court of Appeal issued a decision this week in a case called Birch v. Union of Taxation Employees.  It involved an attempt by the union to collect in court a fine imposed on two members who crossed the union’s legal picket line during a strike.  The fine arose from the fact that crossing the picket line breached a term of the union’s constitution.  The Supreme Court ruled in Berry v. Pully that a union constitution is a contract, and that each person who joins the union is bound by it.  So it would seem to make some sense at first glance that a person who agrees to a contract term requiring them to not cross a picket line, but who then does so, should be liable for whatver result is called for in the contract.
But the Court of Appeal refused to enforce the contract term.  It ruled that the penalty clause was ‘unconsionable’ and therefore unenforceable.  First, the Court ruled that there is an inequality of power between unions and their members in the negotiation of the contract.  Essentially, the union writes the constitution and workers can either agree or not agree.  Of course, that is true of employment contracts generally in most cases.  The employer has all of the bargaining power, it writes the contract, and employees can either accept the terms or not.   There are a few (very few) cases out there where courts have struck down terms of employment contracts that favoured employers (such as short notice periods) as being unconscionable. 
The court then noted that it is not ‘inequality of bargaining power’ in itself that renders a contract unconscionable, but the abuse of that bargaining power by the imposition of ‘very unfair’ terms.  What are ‘very unfair’ terms is a very subjective test that gives judges wide discretion.  Here, two of the judges found that the amount of the fine (set at the gross wages received by the employees for the days they crossed the picket line) was ‘very unfair’.   One judge, Juriansz J.A., found that the amount was not very unfair.   The test does not help the parties predict what is enforceable and what isn’t.
The case does not appear to rule that penalty clauses in union constitutions are per se unenforceable.  It is just that in this case, the majority believed the amount of the fine was too high.  Thus, little deference is given to the union and its members in defining internal union matters, such as how members should behave during legal strikes. 
The majority noted that there was no evidence that the union suffered harm as a result of its members crossing the picket line.   That part of the decision is a bit odd to me.  If the members of a union vote to strike, but then a bunch of them actually cross the picket line to enable the employer to keep producing, wouldn’t that undermine the union’s efforts to pressure the employer to agree to a better collective agreement?  Quantifying the harm to the union may be difficult, but this is a problem in a lot of contract cases.   The majjority here seems to require the union to actual prove a measurable loss due to members breaking ranks and crossing the picket line.  How can it do that?  The Court doesn’t give much guidance as to what would have been a fine that was not ‘very unfair’.
The other odd part of this decision, noted by the dissenting judge, is that the employees who crossed the picket line could simply have not joined the union or could have renounced their membership before crossing the picket line.  Union membership was not a requirement of employment (it was not a ‘closed shop’).  If they were not members of the union, then the Constitution wouldn’t apply to them.   Yet they chose to remain bound to the contract, including the penalty clause, but then refused to comply with the rules of membership they had agreed to. 
I am not sure that unions do themselves a favour in any event by trying to enforce fines against their members in the courts.  I don’t have a philosophical problem with it –I think people who join unions should comply with the rules of the union, or engage in the union’s democratic processes to try and change them.  But I think it looks bad from a PR perspective, and unions right now have a serious public image problem. Suing your members gives union-bashers (like the National Post, for example) ammunition in their campaigns to paint unions as tyrants, picking on poor defenseless workers.  And I doubt unions benefit much anyways from trying to collect the fines.  Courts aren’t enforcing them.  Ideally, unions could provide sufficient benefits to their members that canceling their membership would be a sufficient punishment for people who violate the union’s Constitution.  Even the majority in this case found that suspending a membership as a punishment is fine.
What do you think?  Should unions fine members who cross their own union’s picket line?  Should courts enforce these fines?