I have been thinking about Pilate's slaughtering of Galileans, as told in Luke 13.1ff. I believe that this incident is the issue over which Pilate and Herod became bitter enemies (Lk23.12). Upon hearing that Jesus was Galilean, Pilate sent Jesus to Herod (who was in Jerusalem; Lk23.6ff). Herod was overjoyed at this, and Pilate and Herod then became friends (Lk23.12).
I find it extremely interesting that since Pilate had such a terrible reputation (cf. Philo, Leg. ad Gaium 38.302), he was courteous enough to allow Jesus to be given over to Herod. Where did this courtesy come from? Was he in that much fear of the Jews over the decisions regarding Jesus? I doubt it. I believe that he was trying to make good with Herod, after having enraged him for slaughtering Herod's people.
Richard reminded me of Matthew's testimony, that Pilate's wife advised him to leave Jesus alone on account of her dream (27.17-19). But this detail is lacking in Luke's story. And because Luke tells so clearly of the schism between Herod and Pilate, and of the incident of Luke 13.1ff., and of their reconciliation, I am compelled to believe that Luke has another explanation in mind: namely, that Pilate was trying to make good with Herod after having slaughtered some of Herod's people. Else, why include the story of 13.1ff. at all, while balancing the animosity and subsequent reconciliation between Pilate and Herod? The pericope of 13.1ff. has more to do with the political landscape leading up to Jesus' arrest and death than with that single otherwise randomly-placed, cryptic incident. And the fact that the people were merely informing Jesus of the incident shows that Luke was more interested in including the pericope than in having Jesus comment on it, as does Jesus' response.
So, if this be correct, what possible indicators in Luke's text might there be?
Perhaps the nobleman of Luke 19.12 is Pilate. He was known to be a violent man (Jos. Ant. 18.3.2[60-62]; 18.4.1-2[87-89]; Philo, Leg. ad Gaium 38.302), and thus was feared and dreaded by his constituents (cf. Luke 19.14, 21). In Jesus' parable of the wicked servant in Luke 19.12ff., the nobleman slays his enemies, "those who did not want me to be king over them". The nobleman commands his subjects to "kill [my enemies] before me". In Josephus (Ant. 18.3.2[60-62]), many Jews ("ten thousands") rose up against Pilate, in revolt, because he used the "sacred money" to "bring a current of water to Jerusalem". Pilate had soldiers armed with daggers surround the Jewish rebels. When the Jews would not go away at his bidding, he signaled the soldiers, and they slew the Jewish rebels (though Pilate did not mean for such a severe attack to take place). The soldiers slaughtered both the guilty and innocent. As a result, a "great number of them were slain...and thus an end was put to this sedition." In essense, these Jewish rebels were slain "before Pilate", just as those in Jesus' parable were slain "before [the nobleman]".
Whiston, in footnote, suggests that these Jews "may very well be those very Galilean Jews, 'whose blood Pilate had mingled with their sacrifices' (Luke 13.1-2)" (fn 553). Recall that Pilate queried as to whether or not Jesus was Galiliean (Luke 23.6-7). As a proof that the episode above corresponds to Luke 13.1, Whiston cites Noldius (de Herod. No. 249): "The cause of the enmity between Herod and Pilate seems to have been this, that Pilate had intermingled with the tetrarch's jurisdiction, and had slain some of his Galilean subjects [cf. Luke 13.1]; and, as he was willing to correct that error, he sent Christ to Herod this time" (Whiston, fn 553). So, apparently, Herod and Pilate were at odds with one another, but had made amends when Pilate sent Jesus to Herod (Luke 23.12 [cf. vv.6-7]).
(I have written about the possible significance of Pilate's misuse of the sacred money here.)