There are really three categories:
1. Inadmissible (applies to evidence obtained, for example, by illegal means)2. Illegal (applies to actions specifically not allowed by law)
3. Criminal (apples to some, but not all, illegal actions)
In this case, the statements produced during interrogation and while in police custody were inadmissible under Italian law (under but not limited to, for example, CPP Articles 63, 64, and 188) and Constitution, and not usable for a trial leading to conviction under the ECHR case-law (Salduz, Brusco, Dayanan, and Ibrahim). The actions of the police were illegal, but only some of their actions, such as threats and violence to produce a false statement by a person to be given to a judicial authority, would be subject to criminal charges and penalties (under but not limited to, for example, CP Article 377-bis). The continued framing (official misconduct) directed against Amanda and Raffaele were likely to have been motivated by a desire by the police and their colleagues in the judiciary to avoid criminal charges being brought against the police. If convicted of such charges, an individual could be sentenced, IIRC, to prison for a term of 2 to 6 years.
CP Article 377-bis
Google Translation
Art. 377-bis.
Induction to not make statements or to make false statements to the court [judicial authority]. (1)
Unless the act constitutes a more serious offense, anyone with violence or threats, or offers or promises of money or other benefits, leads to not make statements or to make false statements to the person called to testify before the court [judicial authority] evidence in the criminal proceedings, when it has the right to remain silent, is punished with imprisonment from two to six years.
(1) Article inserted by art. L. 20 of March 1, 2001, n. 63