The Justice Department refused Sen. Ted Cruz’s request for a special prosecutor to investigate the Internal Revenue Service’s illegal targeting of conservative groups, a decision the Texas Republican said was hypocritical and politically motivated.

The DOJ is already investigating the tax agency for singling out groups for special scrutiny that included the conservative buzzwords “Tea Party,” “patriot” or “9/12” in their names.

But Cruz wants a special prosecutor to lead the case after accusing the Obama administration of slow-walking the probe and falling short of its promise to hold accountable those responsible for wrongdoing.

Principal Deputy Assistant Attorney General Peter Kadzik said a special prosecutor wasn’t necessary because the department has faith in its process and the agents handling the case.

“This investigation has been and will continue to be conducted by career prosecutors that are designed to ensure the integrity of an ongoing criminal investigation,” wrote Kadzik in a letter to Cruz.

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