How a Utility Rate Case Works Before the Louisiana Public Service Commission

A rate case notice just landed on your desk, and now your board, your customers, and probably a reporter or two want to know what it means.

The Louisiana Public Service Commission doesn’t decide these cases overnight, and it doesn’t move like a courtroom drama either. It runs through a set order: filing, notice, discovery, hearing, order. Missing a step early can cost you ground before anyone argues the merits.

The attorneys at Marionneaux Kantrow, LLC have guided Louisiana utilities and cooperatives through that order for almost three decades. Here’s how it works, step by step.

Key Takeaways

• A Louisiana rate case moves through five phases: filing, notice and intervention, discovery, hearing, and a Commission order
• Under Article IV, Section 21 of the Louisiana Constitution, a utility can often start collecting an interim increase before the case is decided
• Parties typically get 15 days from the LPSC’s Official Bulletin notice to file for intervention
• LPSC Staff audits the utility’s revenue requirement and reviews cost prudence before any hearing takes place

If a rate filing already has your name on it, Marionneaux Kantrow, LLC can walk you through the timeline before the next deadline passes.

What a Utility Rate Case Decides

A rate case is the formal process the Louisiana Public Service Commission (LPSC) uses to decide whether a utility can change what it charges customers, and by how much. The Commission tests whether the requested revenue matches what it costs to serve customers this year, no more and no less. Everything else in the case, the testimony, the audits, the hearing, exists to answer that one question well enough for the Commission’s five elected commissioners to sign an order and defend it if it’s ever appealed.

Filing the Application and Setting the Test Year

Every rate case starts with an application, filed alongside testimony from company witnesses on costs, revenues, and the return the utility needs to attract capital. Under Louisiana Law, the LPSC has power to fix and regulate rates for nearly every gas, electric, water, and local public utility in the state, and the Commission is domiciled at the state capital in Baton Rouge.

The Revenue Requirement

The application has to justify one number, the revenue requirement, built from operating expenses, depreciation, taxes, and a fair return on invested capital. Some utilities skip a full filing every year by operating under a Formula Rate Plan, an adjustment tied to an earnings test instead of a ground-up case.

The Test Year

Almost every figure is built around a test year, a twelve-month period treated as normal, ongoing costs. Pick the wrong one, or let one-time expenses slip in unadjusted, and the whole revenue requirement is compromised before the case reaches a hearing.

Notice, Publication, and Who Can Intervene

Once the application is filed, the LPSC publishes notice in its Official Bulletin and in the official journal for every parish the case affects. That notice starts the clock for anyone who wants a seat at the table. Parties who typically intervene include:

• Industrial and commercial customers with enough load to feel a rate change directly
• Competing or neighboring utilities with a territorial or wholesale stake in the outcome
• Municipalities, parishes, or consumer groups representing residential ratepayers
• LPSC Staff, which shows up as a party in nearly every contested case

Fifteen days from that notice is the window that shows up most often for filing to intervene. Miss it, and you’re reading the record from outside instead of shaping it.

If a rate case naming your business shows up in the Official Bulletin, talk to a utility rate case attorney at Marionneaux Kantrow, LLC before that deadline passes.

Discovery, Staff Audits, and the Weight of a Prudence Review

Once the parties are seated, the case moves into discovery, where most rate cases get decided, not at the hearing everyone pictures. Intervenors and Staff send data requests, sometimes hundreds of them, testing every line of the cost of service study. Staff auditors run their own prudence review, checking whether spending decisions were reasonable when the utility made them, using information available at the time.

Most firms writing about this process have never sat across from LPSC Staff during that review. Marionneaux Kantrow, LLC has represented utilities and cooperatives through that exact exchange, from the first data request to a Louisiana Supreme Court argument when a dispute escalated that far, a vantage point that shapes how a case gets built from day one.

A weak answer to one data request can unravel months of preparation.

Interim Rates While a Case Is Pending

A utility doesn’t have to wait out the whole case to start collecting. Article IV, Section 21 of the Louisiana Constitution lets the Commission put a proposed schedule into effect if the Commission hasn’t rendered a decision in 12 months, in whole or in part, while the application is pending, as long as the utility posts a protective bond.

That security matters, since interim relief isn’t free money. Under R.S. 45:1163.1, if the final decision comes in lower than the interim rate, the utility owes customers a full refund with interest.

The Hearing, the Commission’s Vote, and What Comes After

Every contested rate case reaches a hearing, held under the LPSC’s Rules of Practice and Procedure, where witnesses are cross-examined, and the record gets built into something the Commission can vote on.

The Hearing and the Recommendation

Live testimony fills gaps the paper record left open. An administrative law judge typically issues a recommendation for the Commission to weigh at its monthly session, and the Commission rarely brushes aside a well-supported one.

Rehearing and Appeal

A losing party can ask for rehearing, and past that, the next stop is district court in East Baton Rouge Parish, where the Commission is domiciled, with the Louisiana Supreme Court as the final word instead of the regular courts of appeal. That’s why it pays to have a utility rate case attorney from Marionneaux Kantrow, LLC involved before the first data request goes out, not after.

FAQs About How Utility Rate Cases Work Before the LPSC

How long does a Louisiana rate case usually take?

Most contested LPSC cases run nine months to two years from filing to final order. Timelines depend mostly on how many parties intervene and how hard discovery gets fought.

Can customers get a refund if the final rate ends up lower than the interim rate?

Yes. Under R.S. 45:1163.1, a utility collecting an interim increase owes a full refund with interest if the final order lands lower.

What’s the difference between a full rate case and a Formula Rate Plan filing?

A full rate case rebuilds the revenue requirement from scratch. A Formula Rate Plan filing is a faster annual check-in against an already-approved earnings test.

Do I need a lawyer to intervene in an LPSC case?

Technically no, but discovery and cross-examination move fast, and parties without counsel fall behind quickly. You’ll want counsel lined up before the 15-day window closes, not during it.

Marionneaux Kantrow, LLC: Your Baton Rouge Energy, Utility & Regulatory Law Firm

A rate case is never just paperwork. It decides your revenue, your customers’ bills, and your board’s confidence in you, built on a record written months before anyone votes.

Attorneys at Marionneaux Kantrow, LLC have sat on that record-building side of Louisiana rate cases for going on three decades, and know which fights in discovery are worth having.

If a case is already filed, or you’re weighing whether to file one, contact our firm today, and let’s map out what comes next.