A federal judge has stepped in to halt a Justice Department investigation targeting Jerome Powell, the chairman of the Federal Reserve, after prosecutors began digging into the costly renovation of the central bank’s offices.

The probe, launched by the Justice Department under Donald Trump’s administration, had focused on the ballooning expenses tied to upgrades at Federal Reserve facilities in Washington, D.C. As part of the investigation, prosecutors convened a grand jury and issued subpoenas seeking records related to the renovation project.

But before investigators could push forward, a federal judge stepped in and halted the effort, blocking the Justice Department from continuing its probe — at least for now.

The move effectively pauses the grand jury’s work and prevents federal investigators from accessing documents tied to the expensive office overhaul, which had drawn scrutiny amid concerns about government spending and oversight.

The Justice Department’s interest in the renovations followed growing questions about how much taxpayer money was involved and whether the project’s costs had expanded beyond initial expectations. With a grand jury already seeking documents, the investigation appeared to be gaining momentum.

Now, however, the judge’s intervention has thrown a major roadblock in the path of federal investigators.

Supporters of the probe argue that examining how federal institutions spend money — especially on large renovation projects — is simply basic accountability. Critics of the investigation, on the other hand, claim it targets the independence of the Federal Reserve.

Either way, the timing of the ruling has already raised eyebrows among political observers. When a grand jury investigation gets shut down just as it begins to gather records, people tend to start asking questions.

And in Washington, transparency and accountability shouldn’t be controversial ideas — even if they sometimes make powerful institutions uncomfortable.