I was just wondering this myself: What happens to your arguments – your sound, cogent, and trenchant arguments – in a motion to dismiss an appeal, after the Court of Appeal summarily dismisses your motion? Are your arguments dead and gone? Or may you raise them again in your respondent's brief?
The answer is: You may re-argue your motion to dismiss in your respondent's brief. And, as was the case in Casey v. Sacramento Public Law Library (D3 Jul. 12, 2021) no. C089936 (nonpub. opn.), the court may re-deny your motion.
In Casey, the library barred the plaintiff from using the self-help center. (Sounds like a story there, but the reader is not let in on it.) The plaintiff sued. Mysteriously, a voluntary dismissal is filed, and the complaint is dismissed. The plaintiff appealed from the dismissal.
Too late, the respondent library argued. The appeal was not filed until more than 180 days after the voluntary dismissal, beyond the outer limit under California Rules of Court rule 8.108. The respondent moved to dismiss, but the Court of Appeal summarily denied that motion.
So the respondent tried again in its respondent's brief. The court said this was permissible:
"Before the record was filed, defendants moved to dismiss the appeal as untimely, and plaintiff opposed the motion. Although we denied the motion, our order does not preclude a later assertion of the issue. (Chernett v. Jacques (1988) 202 Cal.App.3d 69, 71 [initial denial of motion to dismiss “does not evidence this court was able to consider and decide the merits of the dismissability issue in the context of an adequate record and full briefing of the issue”].)"
So this time, the Court of Appeal explained its rationale. But it still refused to dismiss:
"A voluntary dismissal under [Code of Civil Procedure section] 581, subdivision (b)(1) by written request to the clerk is not a final judgment, as no judgment, final or otherwise, is necessary to the dismissal. [Citation.] A voluntary dismissal is a ministerial act, not a judicial act, and not appealable. [Citation.]” (H.D. Arnaiz, Ltd. v. County of San Joaquin (2002) 96 Cal.App.4th 1358, 1364-1365; see also Gutkin v. University of Southern California (2002) 101 Cal.App.4th 967, 974-975.)"
Thus, even if the plaintiff-appellant had filed the request for dismissal, he would not have been required to file an appeal within 180 days from that date.