If you are going to play that way then I will trump your speculation and quote from someone that was in the court room following the trial:
Perugia-shock February 27, 2009
The scientific police finds a palm print on the pillow, not visible at naked eye, and after having checked the database send them the a name. Rudy HermanGuede.
Perugia-shock april 23, 2009
In the police database there are 9 millions record cards with fingerprints and only 1 million with hand-prints too. Thanks to Rudy's usual bad luck, they had taken his palm too.
On the pillow there were 4 bloody signs of fingers/palm. The palm one was readable and, inserted in the data base, resulted Rudy's record card.
Perugia-shock May 8, 2009
Today we came to know something more about the results in respect to Rudi. First of all only the palm print on the pillow is certainly attributable to him. The other ones, which we heard at last hearing, were just probable, so we finally have to consider 1 single print to him.
And then it was revealed something that surprised even the prosecutors. When they inserted the palm print in the database no match came out. Indeed not only Rudi didn't have any criminal record, as we knew, but even when he was stopped in Milan his fingerprints weren't taken.
They got to Rudy only after a while, when the Perugia police sent to Rome the record cards of possible suspected people. Among those cards there was Rudi's one but not for criminal reasons. His finger and palm prints were recorded only because of the law on immigration.