The Democratic-controlled House and Senate this week overwhelmingly overturned Republican Gov. Charlie Baker's recommended changes to the bill.
The governor said those changes would still have let unions work with non-members, charge them for representation, and provide access to the information public employee unions need to communicate with members and non-members.
But Baker opposed language in the bill that would grant union officials access to information like the cellphone numbers of non-union members.
The new law is a response to a 2018 U.S. Supreme Court ruling that threatened to weaken the finances of public sector unions.
A single Republican lawmaker in each chamber opposed the override.
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