Weiss, P. J. Appeal from an order of the Supreme Court (White, J.), entered April 22, 1992 in Montgomery County, which denied defendant John C. Pettinato’s motion to dismiss the complaint against him for want of prosecution.
Plaintiff’s failure to timely comply with defendant’s CPLR 3216 90-day demand resulted in the instant motion to dismiss the complaint for failure to prosecute by defendant John C. Pettinato. To avoid dismissal plaintiff was required to demonstrate a justifiable excuse for his delay in complying with the demand and, in addition, to show that his cause of action had legal merit (see, Mason v Simmons, 139 AD2d 880, 881; Charlotte Lake Riv. Assocs. v American Ins. Co., 130 AD2d 947, lv denied 70 NY2d 605). The showing of merit required an affidavit by one with personal knowledge of the facts and required that materials be included in evidentiary form sufficient to defeat a summary judgment motion (see, Schuman v *989Raymond Corp., 174 AD2d 1040, lv denied 78 NY2d 858; Charlotte Lake Riv. Assocs. v American Ins. Co., supra). We find that the attorney’s affidavit, even when considered with the attached police report of the accident, was insufficient to demonstrate that plaintiff has a meritorious cause of action (see, Zent v Board of Educ., 174 AD2d 1047; Juracka v Ferrara, 137 AD2d 921, 923, lv dismissed 72 NY2d 840; Aquilino v Adirondack Tr. Lines, 97 AD2d 929).
"Certain business records may be received into evidence without having been authenticated by their maker, but only if those records are certified in accordance with CPLR 4518 (c)” (Matter of Peerless Ins. Co. v Milloul, 140 AD2d 346, 347 [citations omitted]). Reliance upon the police accident report by Supreme Court was therefore error (see, supra, at 346; cf., Zuilkowski v Sentry Ins., 114 AD2d 453, 454). Consequently, Supreme Court abused its discretion in denying Pettinato’s motion.
Levine, Crew III, Mahoney and Harvey, JJ., concur. Ordered that the order is reversed, on the law, with costs, motion granted and complaint dismissed against defendant John C. Pettinato.