Defendant's Motion to Augment Expert Witness Designation
Case No.: VCU320906 Date: July 16, 2026 Time: 8:30 A.M. Dept. 1-The Honorable David C. Mathias Motion: Defendant's Motion to Augment Expert Witness Designation Tentative Ruling: To grant the motion.
Facts In this matter, the amended complaint alleges Plaintiff was assaulted at school and struck his head on the asphalt. Plaintiff sues Defendant VUSD on negligence theories. Trial is set for August 17, 2026.
On June 17, 2026, Defendant VUSD filed this motion to augment its expert witness designation. After moving ex parte, this matter was set for hearing July 16, 2026.
Defendant indicates that it timely exchanged its designation of expert witnesses on April 6, 2026. However, in late April of 2026, VUSD states it received the radiology imaging records from Valley Children's Hospital via subpoena following VUSD's subpoena order made on or about October 27, 2025. Additionally, on May 5, 2026, Plaintiff served discovery responses to VUSD's first set of Request for Admissions and VUSD's second set of Form Interrogatories and Request for Production of Documents, which included Plaintiff's production of his radiology records. As such, VUSD did not receive any of Plaintiff's radiology records until after VUSD had already served its expert witness designation on April 6, 2026. Therefore, Defendant seeks to add a neuroradiologist, Dr. Posin, as a retained expert pursuant to Code of Civil Procedure section 2034.620.
Defendant further notes it has met and conferred with Plaintiff, but that Defendant has not received a response to its efforts. Additionally, at the time of filing this motion, none of the expert witnesses have been deposed and the parties have not yet begun noticing the depositions of the experts in this matter. Further, that expert discovery remains open to August 3, 2026 and that Dr. Posin is available for the taking of his deposition.
In an untimely filed opposition, Plaintiff argues that Defendant has known of Plaintiff's traumatic brain injury since the October 2024 government claim, the September 23, 2025 discovery responses identifying traumatic brain injury, concussion, and post-concussion syndrome and including medical and billing records, namely the Valley Children's Hospital radiology report for the CT scan of Plaintiff's brain. Further, that Defendant subpoenaed the radiology records in October 2025 and retained a neuropsychologist on April 6, 2026 who examined Plaintiff. Plaintiff further argues that the production of the films themselves after the initial expert disclosure deadline is insufficient to support the relief in this motion.
Authority and Analysis Code of Civil Procedure section 2034.620 states: The court shall grant leave to augment or amend an expert witness list or declaration only if all of the following conditions are satisfied: (a) The court has taken into account the extent to which the opposing party has relied on the list of expert witnesses. (b) The court has determined that any party opposing the motion will not be prejudiced in maintaining that party's action or defense on the merits. (c) The court has determined either of the following: (1) The moving party would not in the exercise of reasonable diligence have determined to call that expert witness or have decided to offer the different or additional testimony of that expert witness. (2) The moving party failed to determine to call that expert witness, or to offer the different or additional testimony of that expert witness as a result of mistake, inadvertence, surprise, or excusable neglect, and the moving party has done both of the following: (A) Sought leave to augment or amend promptly after deciding to call the expert witness or to offer the different or additional testimony. (B) Promptly thereafter served a copy of the proposed expert witness information concerning the expert or the testimony described in Section 2034.260 on all other parties who have appeared in the action. (d) Leave to augment or amend is conditioned on the moving party making the expert available immediately for a deposition under Article 3 (commencing with Section 2034.410), and on any other terms as may be just, including, but not limited to, leave to any party opposing the motion to designate additional expert witnesses or to elicit additional opinions from those previously designated, a continuance of the trial for a reasonable period of time, and the awarding of costs and litigation expenses to any party opposing the motion.
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Here, as to (a) and (b), the Court agrees that, as no expert depositions have yet been taken and the expert discovery cut off is not until August 3, 2026, Plaintiff will not be prejudiced by the augmentation. Further, Defendant has agreed to permit the retention of an expert by Plaintiff in response to Dr. Posin. This would appear to eliminate any prejudice to Plaintiff. Any reliance on the disclosed neuropsychiatrist is therefore minimal.
Here, the Court finds (c)(1) met by the disclosure of the radiology films after the date of Defendant's disclosure of expert witnesses. Defendant's proposed additional expert is a neuroradiologist that could not have been retained without the radiology records, as opposed to the disclosed neuropsychiatrist. The Court finds sufficient exercise of reasonable diligence as to the subpoenaing of the radiology records and obtaining the May 5, 2026 responses by Plaintiff containing he radiology records and thereafter seeking to retain a neuroradiologist. Further, Plaintiff has sufficient time to depose Dr. Posin and, if necessary, retain their own expert to rebut the opinions of Dr. Posin.
As to (c)(2), the Court finds sufficient inadvertence for having not previously designated an expert based solely on Plaintiff's previous responses to discovery that he had a CT scan of his brain shortly after the incident on May 3, 2024. The Court finds Defendant has promptly, via the meet and confer process, provided sufficient information as to Dr. Posin, the expected topics of testimony and Dr. Posin's qualification.
As to subsection (d), Defendant notes Dr. Posin will be prepared to have his deposition taken prior to trial. Therefore, the Court grants the motion.
If no one requests oral argument, under Code of Civil Procedure section 1019.5(a) and California Rules of Court, rule 3.1312(a), no further written order is necessary. The minute order adopting this tentative ruling will become the order of the court and service by the clerk will constitute notice of the order.
Court reporters are usually not available for law and motion matters in the civil division. The parties and counsel must provide their own reporter if they want a transcript of the proceedings.
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