Editor’s Note: James A. Gagliano is a CNN law enforcement analyst and a retired FBI supervisory special agent. He also serves as an adjunct assistant professor at St. John’s University in Queens, New York. Follow him on Twitter @JamesAGagliano. The views expressed in this commentary are his own.

CNN  — 

Yesterday, CNN reported that over the summer special counsel Robert Mueller had removed an FBI agent from the investigation into the Trump campaign’s possible ties to Russia. Widely touted as experienced in high-level, sensitive investigation supervision, Peter Strzok, a deputy assistant director, had been “laterally transferred” to a post within the Human Resources Department (HRD).

While Strzok may have made a mistake discussing political biases on government devices, his banishment to HRD – the FBI’s equivalent of Siberia – seems unduly harsh. Mueller’s decision may, therefore, be more indicative of a special prosecutor trying to hold onto the reins of his investigation, particularly at a moment when President Donald Trump may feel inclined to intervene. After all, on Friday, his former national security adviser, Michael Flynn, pleaded guilty to lying to the FBI.

James Gagliano

For those unfamiliar with FBI culture, HRD postings are typically an acknowledgement that an agent has exhausted his investigative growth potential, reached a roadblock on the executive development (promotion) ladder or made a misstep that is impossible to recover from.

Prior to Strzok’s demotion, he had worked and supervised innumerable high-profile cases. In fact, former FBI Director James Comey had hand-selected him to lead the investigation into Hillary Clinton’s private e-mail server in 2015.

And Robert Anderson, Jr., the retired executive assistant director at the FBI, and former teammate of mine on the FBI’s Hostage Rescue Team (HRT), tells me that Strzok is one of the finest counterintelligence agents the bureau has ever produced. He insists that the man who served under him in a multitude of deputy positions, and who he promoted several times, would never bring personal biases into an investigation he was overseeing.

According to CNN reports, Strzok exchanged text messages with another bureau senior executive, Lisa Page, who served as an FBI lawyer for Deputy Director Andrew G. McCabe. The Department of Justice’s Office of the Inspector General has been reviewing the communications, some of which are purported to contain derogatory comments about then-candidate Trump – which could have been interpreted as a pro-Clinton bias.

In the FBI, where I served for a quarter-century, we are strictly forbidden from discussing investigation details in texts or e-mails. To do so would make them discoverable, one legal provision that potentially requires the sharing of all relevant documents between plaintiff and defendant attorneys prior to trial.

If the reporting is accurate, Strzok and Page made an unconscionable and inexcusable mistake.

But to Anderson’s point, this is simply not evidence of a tainted investigation. FBI agents are entitled to their own opinions and are allowed to support any political candidate they would like. Yes, there are stringent guidelines that govern this, and the Hatch Act makes it a violation to do any of this on company time. To make partisan comments on government electronic devices while overseeing investigations into both Clinton and Trump can only be described as poor judgment.

However, Strzok’s immediate reassignment – once the texts in question found the light of day – may not simply be due to an obvious error in judgment. Mueller, himself, has been criticized for his prior relationship with Comey, the fact that he was interviewed by Trump for the FBI director position a day before accepting the special prosecutor assignment, and for stacking his prosecution team with lawyers who donated to Democrats and the Clinton campaign in particular.

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    And McCabe, who still currently serves as the FBI’s deputy director, has also come under scrutiny for monies his wife’s failed 2015 campaign for a Virginia state senate seat received from political organizations with ties to Virginia Gov. Terry McAuliffe.

    Mueller’s swift response, upon learning of Strzok’s ill-advised texts, might therefore be a preemptive strike to neutralize some of the criticism and ameliorate some of the image damage his probe has steadily endured from Trump supporters on the right.

    Ergo, Strzok might just be the sacrificial lamb to keep the Russia collusion investigation on track. From here on out, Strzok’s only connection to future probes involving Trump, Clinton or the Kremlin will be limited to making personnel assignments within the FBI’s “Siberia.”