N.J. Blocked by Judge From Disclosing Names of Campaign Donors

New Jersey may not disclose the identities of donors to independent campaign-expenditure committees, a federal judge in a setback for Governor Phil Murphy and transparency activists.

Wednesday’s ruling by U.S. District Judge Brian R. Martinotti in Trenton favored Americans For Prosperity, the libertarian advocacy group backed by Charles Koch and his late brother David Koch, the billionaire industrialists and political activists.

Phil Murphy

Photographer: Allison Joyce/Bloomberg

Murphy in June signed a bill that would make public the sources of money donated to groups seeking to influence local and state elections and public-ballot questions. Such organizations have flourished since the U.S. Supreme Court ruled in ...