The release of congressional testimony by FBI headquarters personnel last week once again focused a light upon bias at the FBI.

The left countered using the following arguments.

Bias always exists; everyone is biased. Therefore evidence of bias is immaterial.

And:

Even if there is bias, this does not mean that actions taken were illegitimate.

If this is true, then, no matter the evidence of bias, investigations and prosecutions that have the color of law are fair, including any of the recent FBI/DOJ investigations (such as those concerning the FISA warrants, Hillary Clinton's exposure of classified material, and of course regarding “Russian collusion”).

One attempted response to the left's argument was made by Fox News legal analyst Gregg Jarrett, who argued that the evident bias of high-ranking FBI personnel “poisoned any chance that the FBI’s investigation of Trump could ever be viewed as neutral, objective and fair.”

But Jarrett's analysis only weakly addresses the left's argument. It leaves room for a rejoinder that whether an investigation appears fair is a question which lies in the eye of the beholder and is thus a partisan matter, subject to a “political charade.” It also does not address the relevance of bias to the correctness of actual investigative steps or prosecutorial actions.

In order to frame a better response, it is necessary to begin with a functional definition of bias in the governmental context we are talking about. Bias, then, is an objectively discernible attitude of a governmental official of sufficient magnitude as to demonstrate that discretionary actions taken by that official, even outwardly unobjectionable ones, were not reliably taken in good faith.

Thus, the left's first argument is easily refuted. Simply, the “background radiation,” “echo of the Big Bang,” kind of bias that the left asserts, probably correctly, that everyone has, is not the kind of bias we are concerned with. Indeed, it is hardly bias at all.

To illustrate: this author worked as a special agent for many years in the FBI and was astounded recently to learn some of the agents he worked most closely with were of a completely different political persuasion from him. Simply, the topic of politics or political affiliation never came up.

Another illustration is that of the recent civil suit that the British political figure Tommy Robinson recently lost. Robinson sued a British police department for violating his human rights by arresting him at a soccer match because they did not like his politics. (This is a separate incident from that for which he was arrested for filming.)

But Robinson lost the case because he could adduce no evidence of bias or of anything unusual about the arrest. Now, as the judge seemed to acknowledge, the police might have been biased regarding Robinson, but if so it was objectively imperceptible.

This is of course correct. Civilized cultures punish neither thought nor even face crimes. (God'll get 'em.)

But in light of the various claims of the left, one must address the situation where there is a biased outlook is clearly evidenced, although the complained-of governmental action is not manifestly unfair, but merely possibly so.

This type of situation is, pace the left, deeply problematic. This is because an otherwise unobjectionable investigative or prosecutorial action can be tainted because of the appearance of bias.

An example can be found in the O.J. Simpson murder trial, where a significant piece of evidence was called into question -- and probably discounted by the jury, resulting in acquittal -- because of the biased-sounding remarks recorded in years previous by the detective who found the evidence. This type of bias is to be condemned, for it can result in miscarriage of justice.

One cannot simply dismiss or ignore this type of bias, since bias of display might well be evidence of bias in deed. Much of the decisions in the justice system are the results of the discretionary powers of law enforcement personnel, and evidence of a bias on the part of the personnel does reasonably poison the system.

Fired agent Peter Strzok sought virulently to discount this type of bias in his own regard. He feverishly, indeed, rabidly, claimed that his own hatred for Donald Trump could not have impacted his decisions, especially, he claimed, because of the system in place at the FBI and DoJ.

Interestingly, Strzok went off on this tirade on his own, not in response to any question.  Then-representative Trey Gowdy's reply was quite amusing: “Agent Strzok, that is a fantastic answer to a question that nobody asked.” (A better retort would have been, “The lady doth protest too much, methinks.”) (Hamlet, III ii)

One should note here that Strzok is exactly wrong yet another reason. If an official greatly detests a person whose matter the official is deciding, it will be hard for him to handle the matter with the requisite good faith. In order to guarantee it, one should remove oneself, or at least seek to. In this regard, Strzok called President Trump a “menace,” “awful,” “loathsome,” a “disaster,” and an “idiot.” The same rule should apply if the official's feelings run in the other direction. (“God Hillary should win 100,000,000 – 0.”)

There is yet a third type of situation involving bias. That is where there is both evidence of bias, that is, of a biased outlook, and of unfair or unusual action. This is where what we are dealing with regarding the various FBI/DoJ scandals of the last two years.

Here evidence of manifest bias helps explain the motives of officials. It is quite important in establishing legitimacy of a prosecutorial or investigative action, in that the criminal law will certainly not reach every such action. Indeed, because so much discretion is given to officials, especially, perhaps, in the justice system, evidence of bias, despite arguments to the contrary, is extremely important. A corrupt official is not merely one who accepts bribes. It includes one who exercises discretionary power corruptly, which is to say, whose discretion is “corrupt.”

Tadas Klimas is a former FBI agent, awarded the National Intelligence Medal of Achievement (NIMA). He may be followed on Twitter @tadas_klimas