By giving employers access to unions' financial information, including strike funds, without requiring employers to reciprocate, the reporting requirements included in Bill C-377 could upset the existing labour relations balance and disadvantage unions in the collective bargaining process.
If two parties are at the table, there are certain measures you wish to hold confidential if you're in a bargaining situation, and that includes how much you have in your strike fund, or how much you have in your replacement worker fund. This information is confidential. The bill would have made it not so, and therefore, significantly negatively impacted the unions in their ability to negotiate.