Plaintiffs commenced this action to recover damages alleged to have resulted from their false arrest and imprisonment by defendant. The trial court granted defendant’s motion for summary judgment, and plaintiffs appeal.
On 18 March 1992 at approximately 7:30 p.m., defendant, a deputy with the New Hanover County Sheriff’s Department, responded to a call regarding a “mental subject.” Defendant met with Doanie Walston, the husband of the “mental subject,” at a gas station and followed Mr. Walston to his home. Mrs. Walston was intoxicated ánd had driven her car through the family’s garage door in a fit of anger. After defendant and Mr. Walston arrived at the Walston residence, Mr. Walston took his young son next door, to the home of plaintiff Shubbin Landen, Jr. Mrs. Walston then ran to Mr. Landen’s home, and defendant followed her inside. At this time, Mr. and Mrs. Landen and their neighbor, plaintiff Darlene Marlowe, were also in the home.
In the Landen home, the Walstons began to push and shove each other. Mr. Landen began yelling at defendant demanding he remove the Walstons from his home. The parties’ accounts differ hereafter. Mr. Landen contends that he had raised his hand to point toward the door and was lowering it when defendant walked toward him, causing the back of Mr. Landen’s fingers to make contact with defendant’s chest. Defendant then informed Mr. Landen that he was under arrest for assaulting an officer. Defendant contends that as he was trying to *127calm the Walstons, Mr. Landen shoved him lightly on his right arm with the palm of his hand.
Mrs. Marlowe contends that upon hearing defendant place Mr. Landen under arrest, she lightly touched her hand to defendant’s forearm to get his attention and asked defendant why he was arresting Mr. Landen. Defendant contends that Mrs. Marlowe screamed at him and shoved him lightly, with the “heel of her hand” contacting his right forearm. Thereafter, defendant placed Mrs. Marlowe under arrest for assaulting an officer. Plaintiffs were tried for these offenses and were found not guilty. Later, they instituted this action against defendant.
On appeal, plaintiffs contend that the trial court erred in granting summary judgment for defendant. Defendant contends that he is immune from suit and that summary judgment was therefore properly granted.
 Plaintiffs commenced this suit against defendant in both his official and individual capacities. We first address the claim against defendant in his official capacity. Plaintiffs contend that defendant is not immune in his official capacity because New Hanover County has purchased liability insurance, thereby waiving governmental immunity.
A county may waive its immunity by purchasing liability insurance to the extent of the insurance coverage. N.C.G.S. § 153A-435(a) (1991). Plaintiffs alleged in their complaint that New Hanover County had a policy of insurance which covered suits for false arrest and imprisonment and that to the extent of that coverage, the county had waived governmental immunity. In his answer, defendant admitted that the county had an insurance policy at the time in question, but denied the allegations regarding the coverage of the policy. Neither side offered the insurance policy as evidence at the hearing on summary judgment. Defendant contends that his denial of the allegations as to coverage in his answer was sufficient to shift the burden at summary judgment to plaintiffs to produce the policy. We disagree.
Regardless of who has the burden of proof at trial, upon a motion for summary judgment the burden is on the moving party to establish that there is no genuine issue of fact remaining for trial and that he is entitled to judgment as a matter of law. First Federal Sav. & Loan Ass’n v. Branch Banking & Trust Co, 282 N.C. 44, 51, 191 S.E.2d 683, 688 (1972). Thus, a defendant moving for summary judgment assumes *128the burden of producing evidence of the necessary certitude which negatives the plaintiff’s claim. Clodfelter v. Bates, 44 N.C. App. 107, 111, 260 S.E.2d 672, 675 (1979), disc. review denied, 299 N.C. 329, 265 S.E.2d 394 (1980). Until the moving party makes a conclusive showing, the non-moving party has no burden to produce evidence. Virginia Elec. & Power Co. v. Tillett, 80 N.C. App. 383, 385, 343 S.E.2d 188, 191, cert. denied, 317 N.C. 715, 347 S.E.2d 457 (1986). Here, defendant had the burden as the moving party to produce evidence showing the lack of insurance coverage, and defendant came forth with no such evidence even though the county had the policy and could easily have produced it. Because defendant failed to show that there was no genuine issue of material fact regarding insurance coverage and that he was entitled to judgment as a matter of law, defendant was not entitled to summary judgment based on immunity as to the claims against him in his official capacity.
 We next address the claims against defendant in his individual capacity. The general rule is that a public official is immune from personal liability for mere negligence in the performance of his duties, but is not immune if his actions were corrupt or malicious or if he acted outside and beyond the scope of his duties. Slade v. Vernon, 110 N.C. App. 422, 428, 429 S.E.2d 744, 747 (1993). A deputy Sheriff in the performance of his investigative and arrest duties is a “public official.” See Messick v. Catawba County, 110 N.C. App. 707, 718, 431 S.E.2d 489, 496, disc. review denied, 334 N.C. 621, 435 S.E.2d 336 (1993).
In the instant case, plaintiffs contend that defendant’s actions were malicious. “A defendant acts with malice when he wantonly does that which a man of reasonable intelligence would know to be contrary to his duty and which he intends to be prejudicial or injurious to another.” Grad v. Kaasa, 312 N.C. 310, 313, 321 S.E.2d 888, 890 (1984). An act is. wanton when it is done of wicked purpose, or when it is done needlessly, manifesting a reckless indifference to the rights of others. Id. at 313, 321 S.E.2d at 891. Plaintiffs have made no forecast of evidence which would tend to show that defendant intended his actions to be prejudicial or injurious to them. At most, plaintiffs’ evidence tends to show that defendant negligently believed he had probable cause to arrest plaintiffs. Accordingly, summary judgment was properly granted for defendant as to the claims against him in his individual capacity.
*129  Despite our conclusion that a genuine issue of material fact exists as to the county’s waiver of immunity, summary judgment for defendant in both capacities would still have been proper if defendant showed there was no genuine issue of material fact as to plaintiffs’ claims of false arrest and imprisonment and that defendant was entitled to judgment as a matter of law.
False imprisonment is the illegal restraint of a person against his will. Fowler v. Valencourt, 334 N.C. 345, 348, 435 S.E.2d 530, 532 (1993). A restraint is illegal if not lawful or consented to. Id. A false arrest is an arrest without legal authority and is one means of committing a false imprisonment. Myrick v. Cooley, 91 N.C. App. 209, 212, 371 S.E.2d 492; 494, disc. review denied, 323 N.C. 477, 373 S.E.2d 865 (1988). The existence of legal justification for a deprivation of liberty is determined in accordance with the law of arrest, which is set forth in Chapter 15A of the General Statutes. Id.
N.C.G.S. § 15A-401(b)(l) (Cum. Supp. 1994) provides that an officer may arrest a person without a warrant if the officer has probable cause to believe that the person has committed a criminal offense in the officer’s presence. A warrantless arrest without probable cause is unlawful. State v. Zuniga, 312 N.C. 251, 259, 322 S.E.2d 140, 145 (1984). Thus, the dispositive issue is whether defendant had probable cause to believe that plaintiffs had committed assaults upon him.
The existence or nonexistence of probable cause is a mixed question of law and fact. Williams v. Boylan-Pearce, Inc., 69 N.C. App. 315, 319, 317 S.E.2d 17, 20 (1984), aff'd per curiam, 313 N.C. 321, 327 S.E.2d 870 (1985). If the facts are admitted or established, it is a question of law for the court. Id. However, if the facts are in dispute, the question of probable cause is one of fact for the jury. Id. In this case, the material facts surrounding the incident are in dispute, and therefore the existence or nonexistence of probable cause is for the jury to determine. Accordingly, defendant was not entitled to summary judgment on this ground.
For the reasons stated, the trial court’s order of summary judgment is affirmed as to defendant in his individual capacity and reversed as to defendant in his official capacity, and the case is remanded to the trial court for further discovery or trial.
Affirmed in part, reversed in part, and remanded.
Judge MARTIN, Mark D. concurs.
*130Judge GREENE dissents in part and concurs in part.