Colstrip Power Plant (Photo by Darrell Ehrlick of the Daily Montanan).

NorthWestern Energy continues to treat oversight by the Montana Public Service Commission and engagement with stakeholders as “afterthoughts” — part of a “disturbing pattern” by the state’s largest public utility, a lawyer representing a conservation watchdog argued Tuesday.

The Public Service Commission regulates monopoly utilities in Montana, but NorthWestern Energy leaves the agency in the dark, fails to ask it for approvals, and fires off requests at the last minute without adequate information, said Jenny Harbine, representing the Montana Environmental Information Center.

In this case, NorthWestern wants the Public Service Commission to approve a request that it be allowed to temporarily tap a customer credit to

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