*412 OPINION
In this case, we decide whether a county employee, sued independently from his employer, may assert official and sovereign immunity as defenses against a tort claim. Robert Earl Davis sued two Ellis County deputy sheriffs in then’ individual and official capacities based on events surrounding his arrest for telephone harassment and the eventual dismissal of the charges against him. One of the deputy sheriffs, O.D. Smith, Jr., brings this interlocutory appeal challenging the trial court’s refusal to grant him summary judgment on Davis’s claim against him for malicious prosecution. Smith contends the trial court erred in not concluding as a matter of law that he was immune from liability in both his individual and official capacities. On the undisputed facts presented, we agree the trial court erred in not granting summary judgment to Smith in his individual capacity under the doctrine of official immunity. But we also conclude Smith was not entitled to summary judgment in his official capacity under the doctrine of sovereign immunity because that affirmative defense was reserved in this case only to Ellis County, which was never made a party in Davis’s suit. The trial court, therefore, did not err in denying Smith summary judgment in his official capacity.
I.
In October 1993, Sue Sherrard called the Ellis County Sheriffs Office to complain about a bill collector named Larry Johnson. Sherrard stated that Johnson worked with a collection agency called Hamilton-Phelps & Associates and he had been harassing her in an attempt to collect a débt owed by her son. Smith and another officer, Clint Tims, were assigned to investigate the complaint.
Smith telephoned Johnson at his office and asked him to tell his side of the story. According to Smith, Johnson responded angrily, cursed at him, and hung up. Smith then asked Tims to call Johnson. Johnson gave Tims an equally angry response. After Johnson hung up on Tims, Tims immediately telephoned again and asked the receptionist to put him through to the office supervisor. Tims was transferred to a man named Chaston Howell. Tims stated that Howell’s voice sounded identical to Johnson’s. After Tims identified himself and the purpose of his call, Howell made some rude remarks and hung up. Tims then called the office a third time and asked to speak to Howell again. The man Tims spoke to this time made some specific, disparaging remarks and hung up. Gregory Hamilton, a principal of Hamilton-Phelps & Associates, later admitted he was the person who made the disparaging comments to Tims.
Smith made an appointment to see Sher-rard that afternoon. During his visit with her, Smith took a written statement in which Sherrard stated that Johnson had been calling her six or seven times a day in connection with her son’s debt. Sherrard stated that Johnson used foul language and was abusive and threatening. Sher-rard repeatedly told Johnson to stop calling her, but he continued to do so.
Three days after obtaining the statement from Sherrard, Smith prepared and signed a complaint against Johnson as well as an affidavit to obtain an arrest warrant for Johnson. Smith presented the affidavit to a magistrate. In his summary judgment affidavit, Smith stated that, in addition to the information contained in the affidavit in support of the arrest warrant, he told the magistrate that the name “Larry Johnson” possibly was an alias. Both Smith and Tims testified they had interviewed a collection agent from another company who told them that bill collectors often use assumed names. The arrest warrant, however, was issued only for the arrest of “Larry Johnson.”
After obtaining the signed warrant, both Smith and Tims went to the collection agency. Upon entering the office, Smith *413 saw a box with the name Larry Johnson on it. Smith told the receptionist he wanted to see Johnson. Although the facts concerning what occurred after this point are in dispute, Davis, who was also employed by the agency, walked into the office at that time. Smith and Tims placed Davis under arrest believing he was the man they had spoken to on the phone and who had been harassing Sherrard. Both officers testified they recognized Davis’s voice as the same one they heard over the phone when talking to “Larry Johnson.” Davis contends he repeatedly informed the officers that he was not Larry Johnson and that he provided them with proof of his identity after his arrest. Hamilton testified that a man named Larry Johnson was, in fact, employed by his agency and working on the Sherrard account. The harassment charge brought against Davis was later dismissed because Sherrard was unable to identify Davis as the man who had been harassing her.
After the harassment charge was dismissed, Davis brought this civil action against Smith and Tims in both their individual and official capacities as deputy sheriffs of Ellis County. Davis did not sue Ellis County itself. Davis alleged claims for false arrest, false imprisonment, and assault and battery against both Smith and Tims. In addition, Davis asserted a claim for malicious prosecution against Smith alone.
Smith and Tims moved for summary judgment on all of Davis’s claims arguing several grounds, including official and sovereign immunity. The trial court granted summary judgment in their favor on all claims except the claim against Smith for malicious prosecution. Smith now brings this interlocutory appeal pursuant to section 51.014(5) of the Texas Civil Practice and Remedies Code contending the trial court erred in failing to hold that he was immune from liability on the malicious prosecution claim in both his individual and official capacities.
II.
In examining Smith’s contentions on appeal, we recognize that the malicious prosecution claim against him in his individual capacity is separate and distinct from the claim against him in his official capacity. A suit against a government employee in his individual capacity seeks to impose personal liability on the employee for actions he takes under color of state law.
See Kentucky v. Graham,
Each capacity involves a separate and distinct form of potential immunity. Government employees sued in their individual capacity may claim the protections of official immunity. Gross
v. Innes,
To be entitled to official immunity, Smith was required to show that the claim for malicious prosecution arose out of his performance of discretionary duties that were done in good faith and within the scope of his authority.
See Kmiec,
A person “initiates” a criminal prosecution when he makes a formal charge.
Lieck,
An act is discretionary if it involves personal deliberation, decision making, and judgment.
Kmiec,
To establish that his initiation of the criminal prosecution was done in good faith as a matter of law, Smith was required to show that a reasonably prudent officer, under the same or similar circumstances, could have believed his actions were justified.
City of Dallas v. Aguirre,
Good faith may be established by the testimony of the defendant officer if the testimony is clear, positive, direct, otherwise credible, free from contradiction, and readily controvertible.
Wait-man,
at 637-38. Conclusory statements about acting in good faith are insufficient. The officer must provide adequate substantiation that a reasonably prudent officer in his position could have believed the actions taken were justified.
See Wadewitz v. Montgomery,
To controvert summary judgment proof of good faith, a plaintiff must show that no reasonable person in the defendant’s position could have thought the facts were such that they justified the defendant’s acts.
Chambers,
In response to the motions for summary judgment, Davis filed several affidavits including one by his expert on police work. It is in this affidavit that the issue of Smith’s good faith is addressed by Davis. Although the affidavit contains no statements concerning Smith’s filing of the complaint, the expert addressed the arrest warrant by testifying that “no reasonable officer who believed that Larry Johnson might be an alias would have neglected to inform the magistrate of that fact at the time he was seeking an arrest warrant and no reasonable officer who suspected that Larry Johnson was an alias would have had that warrant issued without it reading John Doe aka Larry Johnson.” This testimony does not raise a fact issue about Smith’s good faith in initiating criminal proceedings against a man he believed was using the name Larry Johnson. If anything, the expert’s testimony is evidence only of negligence in the manner in which the arrest warrant was filled out. Evidence of negligence alone does not controvert competent evidence of good faith. Id. at 469 n. 1.
Smith presented sufficient summary judgment evidence to demonstrate his entitlement to official immunity as a matter of law. Davis failed to raise a fact issue with respect to this affirmative defense. Therefore, Smith was entitled to the protections of official immunity. We conclude the trial court erred in failing to grant summary judgment to Smith in his individ *416 ual capacity. We next address whether Smith was entitled to summary judgment in his official capacity.
As we said above, a suit against a government employee in his official capacity is distinctly different from a suit against him in his individual capacity. In suing an employee in his official capacity, a plaintiff seeks, in effect, to impose liability on the governmental unit the employee represents, rather than on the employee himself.
See Harris County v. Walsweer,
When the governmental unit is a party to the suit, the employee may enjoy derivatively the protections and immunities of his employer.
See Kmiec,
Sovereign immunity is the doctrine under which the government is not answerable to suit or to damages unless it consents to be sued.
Gonzalez v. Heard, Goggan, Blair & Williams,
When sued, a governmental unit that wants to claim sovereign immunity should plead the immunity as an affirmative defense.
See
Tex.R. Civ. P. 94. Like other affirmative defenses, sovereign immunity may be waived if not pled. Because the immunity protects only the sovereign, only the sovereign is entitled to claim the defense or, possibly, decide to waive it by not affirmatively pleading it. Only after the sovereign pleads and proves the defense can the employee assert that the suit against him in his official capacity fails.
See Kmiec,
If individual employees were allowed to invoke the protections of sovereign immunity in tort cases where they were sued independently of the governmental unit that employed them and without the government’s joinder in the suit, the employees would be directly litigating an immunity which protections they are only derivatively entitled to claim. An em *417 ployee independently urging the defense of sovereign immunity would be virtually attempting to represent the interests of his non-party, governmental employer. Because the employee is not personally liable for a judgment rendered against him in his official capacity, the employee may have very little incentive to defend against those claims or to represent his employer’s interests vigorously.
Furthermore, any adjudication of the defense of sovereign immunity without the sovereign having the opportunity to be present and defend itself would be an advisory opinion on the governmental unit’s immunity or lack of it. It is well established that the courts of this state are not empowered to give advisory opinions.
Patterson v. Planned Parenthood, Inc.,
In addition to Smith’s appeal, Davis brought a cross-appeal contesting the trial court’s granting of summary judgment on the other claims brought against both Smith and Tims. Because this appeal is interlocutory, we have no jurisdiction to address Davis’s issues now.
See Richardson v. Parker,
We reverse the trial court’s denial of summary judgment on the issue of official immunity and render judgment that Davis take nothing by his claim for malicious prosecution against Smith in his individual capacity. We affirm the trial court’s denial of summary judgment on the claim for malicious prosecution against Smith in his official capacity because Smith’s claim of sovereign immunity was a request for relief the trial court could not grant him and, also, was a request for an advisory opinion on Ellis County’s sovereign immunity. We remand the claim to the trial court for further proceedings.
Notes
. Davis also alleged that Smith committed the tort of malicious prosecution by falsely arresting him. Assuming that a claim for false arrest could form the basis of a claim for malicious prosecution, Smith received summary judgment in his favor on the claim against him for false arrest. Accordingly, this claim will not be discussed further in this interlocutory appeal.
. We express no opinion on the merits of a claim for malicious prosecution based solely on the act of filing an affidavit for an arrest warrant.
.
But see Liberty Mut. Ins. Co. v. Sharp,
