NIPSCO lawsuits and legal actions currently span four fronts: a state regulatory investigation into thousands of overcharged natural gas customers, a request that Indiana’s Attorney General open a deceptive-practices probe, a pending Indiana Supreme Court appeal over how the utility recovers infrastructure costs, and a federal court challenge to a U.S. Department of Energy order that forced two of NIPSCO’s coal units to keep running past their retirement date. A separate federal consent decree governs NIPSCO’s ongoing cleanup of a coal ash Superfund site in Porter County. Together, these cases sit on top of two back-to-back electric rate increases that pushed the average residential bill up sharply between 2023 and 2026.
Gas Meter Overcharging Investigation
The most immediate legal exposure involves NIPSCO’s natural gas meters. In late October 2024, the company discovered that a number of its mechanical meter indexes had an “improper drive rate configuration” that produced incorrect readings. More than 3,500 customers were overcharged, with some billed for roughly twice the natural gas they actually used.1WNDU. Michiana Area State Senator Requests Investigation Into NIPSCO Billing Discrepancies
NIPSCO issued bill credits to affected customers but did not tell them what the credits were for, and it did not notify the Indiana Utility Regulatory Commission’s chief of staff until September 17, 2025, nearly a year after discovery. The first formal meeting with the Commission came on November 19, 2025.2The Indiana Lawyer. State Senator Asks Rokita to Investigate NIPSCO for Deceptive Consumer Practices IURC General Counsel Beth Heline said a “not-insignificant number” of meters were affected and that NIPSCO failed to “proactively provide notice or explanation to the affected customers.”3WANE. NIPSCO Responds to Investigation Involving Excessive Bills for Customers
On November 26, 2025, the IURC opened a formal investigation under Cause No. 46329.4Indiana IURC. Order Initiating Investigation, Cause No. 46329 NIPSCO responded publicly that the issue affected “less than 1% of NIPSCO’s natural gas customers,” was not caused by its new advanced metering technology, and that it would refund 12 months of usage per IURC rules.3WANE. NIPSCO Responds to Investigation Involving Excessive Bills for Customers
A prehearing conference was held on January 15, 2026, and NIPSCO was required to file testimony by March 2, 2026. An evidentiary hearing initially scheduled for July 2, 2026 was suspended, and the case remains pending. The Citizens Action Coalition and the Office of Utility Consumer Counselor are participating as intervenors.5Indiana IURC. Docketed Case Details, Cause No. 46329
Request for an Attorney General Investigation
The delayed disclosure prompted State Senator Mike Bohacek (R-Michiana Shores) to formally ask Indiana Attorney General Todd Rokita to investigate whether NIPSCO’s conduct violated Indiana’s deceptive consumer sales statute. Senators Rick Niemeyer, Rodney Pol Jr., and Dan Dernulc, along with Representative Randy Novak, cosigned the letter. Bohacek wrote that he was “extremely” alarmed that NIPSCO may have known about the faulty meters and failed to disclose the problem in a timely manner.1WNDU. Michiana Area State Senator Requests Investigation Into NIPSCO Billing Discrepancies
As of mid-2026, the Attorney General’s Office had not publicly said whether it would open a formal investigation.2The Indiana Lawyer. State Senator Asks Rokita to Investigate NIPSCO for Deceptive Consumer Practices
Electric Rate Increases Behind the Backlash
The regulatory scrutiny is unfolding against a backdrop of large rate increases. In September 2022, NIPSCO asked the IURC for a $395 million electric revenue increase. A March 2023 settlement trimmed roughly $103 million from that request, holding the residential bill increase to $12.37 per month when fully phased in and setting the monthly customer charge at $14.00. The IURC approved the deal on August 2, 2023.6Indiana OUCC. NIPSCO Electric Rate Case 2022/2023
NIPSCO filed again in September 2024, seeking another $368.7 million. The OUCC concluded only about $203.2 million was justified.7WKVI. OUCC Makes Recommendations in NIPSCO’s Electric Rate Case A February 2025 settlement cut the increase to approximately $257 million with a 9.75% return on equity, and the IURC approved it on June 26, 2025. For a typical residential customer using 672 kWh per month, that works out to a bill increase of roughly 16.75%, phased in over two steps.8NIPSCO. IURC Order, Cause No. 46120
The Citizens Action Coalition opposed the second settlement, calling it “unbalanced” and arguing it pushed disproportionate costs onto residential customers.9Citizens Action Coalition. CAC: IURC Reject Unbalanced NIPSCO Settlement Agreement According to a 2025 IURC survey cited by state legislators, NIPSCO customers using 1,000 kWh in July saw their bills rise by over 90% compared to 2016. The U.S. Energy Information Administration reported NIPSCO as maintaining the second-highest residential customer rate among all reporting electric utilities.1021Alive News. Indiana Representative Calling for Review of NIPSCO Rates
TDSIC Case at the Indiana Supreme Court
A separate legal fight goes to how NIPSCO recovers infrastructure costs outside of a full rate case. The Transmission, Distribution, and Storage System Improvement Charge, or TDSIC, is a mechanism the Citizens Action Coalition has identified as a primary driver of rising bills.11Citizens Action Coalition. NIPSCO Electric Rate Hike 2024
The Indiana Supreme Court already limited how NIPSCO can use that mechanism. In NIPSCO Industrial Group v. Northern Indiana Public Service Co., decided in 2018, the Court held that utilities must identify specific projects at the outset of a TDSIC proceeding to qualify for accelerated cost recovery, rejecting NIPSCO’s approach of getting broad “project categories” approved and defining actual projects later.12Parr Richey. NIPSCO Industrial Group v. Northern Indiana Public Service Co., 100 N.E.3d 234
A new fight is now back before the Court. In 2024, NIPSCO petitioned for a fifth TDSIC rate adjustment and third plan update, which the IURC approved. The NIPSCO Industrial Group, a coalition of six industrial customers including U.S. Steel, challenged that decision, arguing NIPSCO failed to justify inflation-driven spending increases and should have gone through a full base rate case instead. A three-judge panel of the Indiana Court of Appeals unanimously affirmed the IURC in September 2025.13Indiana Capital Chronicle. NIPSCO, Industrial Ratepayers Split on Inflation Cost Recovery Before Indiana Supreme Court The industrial group sought transfer to the Indiana Supreme Court, which heard oral arguments on May 21, 2026. As of that date, the Court had not announced whether it would take the case.14State of Indiana. NIPSCO Industrial Group v. Indiana Office of Utility Consumer Counselor, No. 24A-EX-02834
Federal Court Challenge Over the Schahfer Coal Plant Order
NIPSCO had planned to retire the last coal-fired units at its R.M. Schahfer Generating Station in Wheatfield, Indiana by the end of 2025. On December 23, 2025, the U.S. Department of Energy issued Emergency Order No. 202-25-12 under Section 202(c) of the Federal Power Act, requiring NIPSCO and the Midcontinent Independent System Operator to keep Schahfer Units 17 and 18 available for operation through March 23, 2026.15U.S. Department of Energy. Federal Power Act Section 202(c) Schahfer Order No. 202-25-12 DOE later extended the order through June 21, 2026.16Utility Dive. DOE Extends Emergency Operations at 2 Indiana Coal Plants
On March 17, 2026, the Citizens Action Coalition, Just Transition Northwest Indiana, and the Hoosier Environmental Council, represented by Earthjustice, filed a petition in the U.S. Court of Appeals for the D.C. Circuit seeking to overturn the DOE orders. The groups argued DOE “misused its authority” because there was no actual grid emergency, and that the forced operation was causing unnecessary pollution and driving up electricity costs.17The Indiana Lawyer. Environmental Groups Ask Court to Nullify Order Keeping Indiana Coal Units Firing The petition remains pending.
The costs matter for ratepayers. A Sierra Club analysis estimated the net cost of keeping Schahfer running at approximately $174,000 per day.16Utility Dive. DOE Extends Emergency Operations at 2 Indiana Coal Plants Environmental groups estimated the initial 90-day period alone exceeded $20 million, and NIPSCO has notified the IURC that it intends to seek recovery of those costs from ratepayers across the 11-state MISO grid.18Environmental Law and Policy Center. Groups Challenge Illegal Order Halting the Retirement of Indiana Power Plants
Town of Pines Coal Ash Consent Decree
NIPSCO is also under a federal consent decree tied to coal ash contamination at the Town of Pines Groundwater Plume Superfund site in Porter County, Indiana. Coal ash from a NIPSCO generation facility was placed in the “Yard 520” landfill and used as construction fill in the surrounding community starting in the 1970s. Testing found hazardous levels of arsenic, thallium, and lead in residential soil.19U.S. EPA. Northern Indiana Public Service Company to Clean Remaining Surface Contamination, Town of Pines
Under a consent decree lodged in the U.S. District Court for the Northern District of Indiana in March 2022, NIPSCO is required to spend an estimated $11.8 million to identify and excavate contaminated residential soil, restore properties with clean backfill, put land-use restrictions in place, and monitor wells, surface water, and sediments. The company must also reimburse a large percentage of past EPA costs and pay all future oversight costs for both the EPA and the State of Indiana.20ECOS. Indiana Company Enters Settlement to Clean Up Surface Contamination Earlier remediation dating back to 2003 connected roughly 270 homes to municipal water; as of 2022, 38 homes remained unconnected.21Great Lakes Now. Indiana Residents Coal Ash Cleanup
If You Think You Were Overcharged
The gas meter case is the one most likely to affect an individual customer’s wallet directly. NIPSCO has said it is correcting impacted bills and will issue refunds covering 12 months of usage under IURC rules.3WANE. NIPSCO Responds to Investigation Involving Excessive Bills for Customers Customers who believe they were affected can review recent bills for unexplained credits, contact NIPSCO for an explanation, and file a complaint with the Indiana Office of Utility Consumer Counselor, which is intervening in the IURC investigation on the consumer side.5Indiana IURC. Docketed Case Details, Cause No. 46329 The pending investigation could produce additional remedies beyond the 12-month refund window; that outcome is not yet decided.