A YEAR or two ago, a top official from Prince George’s County’s Office of Ethics and Accountability, established in 2012 to address the woeful local record of public corruption, delivered a standard training session at the liquor board, a state body that regulates alcohol sales at more than 600 county restaurants, liquor stores and other businesses. Apparently, the lesson didn’t stick.

Federal prosecutors, working with the FBI, said last week they have charged two liquor board officials, in addition to a pair of liquor store owners, in what they described as a long-running shakedown scheme that involved cash bribes to public officials for services rendered.

In addition to those charges, William A. Campos, a former state lawmaker and County Council member, pleaded guilty to accepting bribes in exchange for official favors — one of the maladies that seem to infect elected officials in Prince George’s with unsettling frequency. Papers filed in U.S. District Court in Greenbelt made it clear that another current state lawmaker, whose identity has not been announced, is also expected to face criminal prosecution in the racket.

The small-time sleaze practically seeps out of the documents filed by prosecutors — for instance, cash bribes of $1,000 and $3,000, nestled in white envelopes and slipped, allegedly, to sticky-palmed officials. The payoffs are said to have been rewards for, among other things, legislation enacted in 2015 to grant permits authorizing about 100 county liquor stores to remain open on Sundays.

One issue is the futility of enforced Sunday closures for liquor stores, which deprive owners of income and force local residents to cross county lines to purchase alcohol. That pointless restriction remains partly in place even after the 2015 legislation: Prince George’s has more liquor stores than available permits for Sunday sales.

Gov. Larry Hogan (R) was therefore correct when he suggested that the entire system is ripe for an overhaul. As things stand now, the liquor boards are not really accountable to anyone. Although the governor appoints county liquor board members throughout the state, the candidates are presented to him by local party officials.

Rushern L. Baker III (D), the Prince George’s county executive, took office in 2010 pushing a package of ethics reforms following the depredations of his predecessor, Jack B. Johnson (D), who went to prison for pocketing more than $1.6 million in bribes. Mr. Baker’s reforms were laudable; they curtailed the use of county credit cards and cars and limited campaign donations from developers.

But even the more aggressive reforms he wanted, yet failed to push through — including establishing a county inspector general with subpoena powers — would not have stopped a scandal like the one at the liquor board. Tighter accountability and a merit-based system of selecting board members should replace what Mr. Hogan aptly called “the last vestiges of the patronage system.”