I read that Justin Martyr mentions “the Acts of Pontius Pilate”, and so I looked for Πράξεις τοῦ Ποντίου Πιλάτου. However, what he actually says is this:
καὶ ταῦτα ὅτι γέγονε δύνασθε μαθεῖν ἐκ τῶν ἐπὶ Ποντίου Πιλάτου γενομένων ἄκτων
ἄκτα is a much more interesting word, imo. LSJ Supplement has an entry glossing it as “official records,” and that’s what I assume that it means here. Not quite a simple parallel to the Acts/Πράξεις of the Apostles/John/Paul/Peter/Andrew/Thomas.
The two references to the Acta of Pilate.
Justin Martyr 35–
…καὶ ὁ μὲν Δαυῒδ ὁ βασιλεὺς καὶ προφήτης, ὁ εἰπὼν ταῦτα, οὐδὲν τούτων ἔπαθεν, Ἰησοῦς δὲ Χριστὸς ἐξετάθη τὰς χεῖρας, σταυρωθεὶς ὑπὸ τῶν Ἰουδαίων ἀντιλεγόντων αὐτῷ καὶ φασκόντων μὴ εἶναι αὐτὸν Χριστόν. καὶ γὰρ ὡς εἶπεν ὁ προφήτης, ‘Διασύροντες αὐτὸν ἐκάθισαν ἐπὶ βήματος καὶ εἶπον, Κρῖνον ἡμῖν.’ τὸ δὲ ‘Ὤρυξάν μου χεῖρας καὶ πόδας’ ἐξήγησις τῶν ἐν τῷ σταυρῷ παγέντων ἐν ταῖς χερσὶ καὶ τοῖς ποσὶν αὐτοῦ ἥλων ἦν. καὶ μετὰ τὸ σταυρῶσαι αὐτόν, ἔβαλον κλῆρον ἐπὶ τὸν ἱματισμὸν αὐτοῦ, καὶ ἐμερίσαντο ἑαυτοῖς οἱ σταυρώσαντες αὐτόν. καὶ ταῦτα ὅτι γέγονε δύνασθε μαθεῖν ἐκ τῶν ἐπὶ Ποντίου Πιλάτου γενομένων ἄκτων…
What prophet Justin Martyr is referring to with his, “Διασύροντες αὐτὸν ἐκάθισαν ἐπὶ βήματος καὶ εἶπον, Κρῖνον ἡμῖν,” I have no idea.
Justin Martyr 48–
…Ὅτι δὲ καὶ θεραπεύσειν πάσας νόσους καὶ νεκροὺς ἀνεγερεῖν ὁ ἡμέτερος Χριστὸς προεφητεύθη, ἀκούσατε τῶν λελεγμένων. ἔστι δὲ ταῦτα· ‘Τῇ παρουσίᾳ αὐτοῦ’ ‘ἁλεῖται χωλὸς ὡς ἔλαφος, καὶ τρανὴ ἔσται γλῶσσα μογιλάλων.’ ‘τυφλοὶ ἀναβλέψουσι,’ ‘καὶ λεπροὶ καθαρισθήσονται,’ ‘καὶ νεκροὶ ἀναστήσονται’ ‘καὶ περιπατήσουσιν.’ ὅτι τε ταῦτα ἐποίησεν, ἐκ τῶν ἐπὶ Ποντίου Πιλάτου γενομένων ἄκτων μαθεῖν δύνασθε.
A note on ἄκτα from Oxyrhynchus Papyri 2725.21
If the ἄκτα were ever a circulating document (genuine or not) it’s not impossible that we have them in some form in the synoptic passion accounts, which depart in style a bit from the earlier parts of the synoptics.