Polish officials on Saturday arrested Roman Giertych, a high-profile lawyer, former deputy prime minister of Poland, and staunch critic of the Polish government, on charges of money laundering.

Giertych is accused of laundering the equivalent of USD $23 million, although the specifics behind the allegations have not been revealed.

Giertych’s legal practice includes involvement in major cases against the majority Law & Justice party and representation of prominent opposition figures. He is also a strong critic of the Polish government. This has led to suspicion that his prosecution was politically motivated, especially given the few details revealed regarding Giertych’s arrest.

On Giertych’s Twitter account, someone tweeted on behalf of him that “[t]he court challenged the prosecution’s accusations in the Roman Giertych case. We know the rationale.” This appeared to be a suggestion that the real motivation was retaliation for Giertych’s strong criticism of the government.