Evidence, yes..... but I have grown a little hazy on the explanation of the motivation.
The only one I remember comes from p. 367 of the PMF translation (emphasis added).
Amanda + Raffaele chose evil, because they smoked pot, liked to watch movies, and read comic books.
Why, then, two young people, strongly interested in each other, with intellectual and cultural curiosity, he on the eve of his graduation and she full of interests, resolved to participate in an action aimed at forcing the will of Meredith, with whom they had, especially Amanda, a relationship of regular meetings and cordiality, to the point of causing her death, falls within the continual exercise of choice among [the range of] possibilities, and this Court can only register the **choice of extreme evil ** which was put into practice. It can be hypothesised that this **choice of evil** began with the [393] consumption of drugs which had happened also that evening, as Amanda testified.
On the effects of drugs of the type used by Amanda and by Raffaele, such as hashish and marijuana , [we] heard the testimony of Professor Taglialatela who, while underlining the great subjective variability (page 211, hearing of 17 July 2009) specified that the use of such substances has a negative influence on the cognitive capacity and causes alterations of perception (pages 201 and 207) and of the capacity to comprehend a situation (page 218). In his turn, Professor Cingolani, who together with Professor Umani Ronchi and Professor Aprile, had also dealt with the toxicological aspect (see witness report lodged on 15 April 2008, pages 26 and following), responding to the question he had been asked as to whether the use of drugs lowers inhibitions replied: "That is beyond doubt" (page 163 hearing of 19 September 2009), while correlating that effect to the habits of the person [on] taking the drugs. Raffaele Sollecito's friends had furthermore stated that such substances had an effect of relaxation and stupor.
Therefore it may be deduced that, accustomed to the consumption of drugs and the effects of the latter, Amanda Knox and Raffaele Sollecito participated actively in Rudy's criminal acts aimed at overcoming Meredith's resistance, subjugating her will and thus allowing Rudy to act out his lustful impulses; and this is considered to have happened because, for those [i.e. for people] who did not disdain the use of drugs (Amanda has stated that on that evening, before "making love", they had consumed drugs), watching films and reading comic books in which sexuality is accompanied by violence and by situations of fear, disregarding the concept of sexuality as an encounter of [two] persons moved by reciprocal and free emotion (see the comic books seized from Raffaele Sollecito and the statements on the viewing of films which had drawn the attention of the tutors of the ONAOSI College attended by Raffaele Sollecito), the prospect of helping Rudy in [his] goal of subduing Meredith in order to sexually abuse her may have seemed to be an exciting stimulant which, although unexpected, had to be tried. [394]
A motive, therefore, of an erotic, sexually violent nature which, arising from **the choice of evil** made by Rudy, found active collaboration from Amanda Knox andRaffaele Sollecito.