Right to Silence The right to defend oneself also includes the right not to cooper-
ate with prosecuting authorities: the accused has a right to remain silent, which
means that he should not be compelled (by law or by the prosecuting authorities) to
make statements that could turn out to be detrimental to his case.
Cross-ExaminationThe right to defense incorporates also the possibility to
discredit the evidence offered by the prosecution by confronting the incriminating
witnesses. In the example at the beginning of this chapter, it was the cross-
examination of the counsel combined with the introduction of further evidence
that allowed the innocent Mr M. to escape an unjust conviction.
Fair Investigations The fair trial safeguards are also applicable during the inves-
tigative stage, at least insofar as this is compatible with that earlier phase. In
particular, the rights to legal assistance and to remain silent apply not only to
defendants at trial but also to suspects during the investigative phase.
Proportionality The main principle concerning the investigation stage is the
principle of “proportionality,” which entails that state authorities should not make
arbitrary use of their coercive and intrusive powers.
For instance, searching a house in a case of drunk driving is clearly disproportionate just
like searching all the houses of a city to investigate a robbery. Widespread interceptions of
telephone conversations should not be tolerated even for discovering serious crimes.
In other words, investigative measures cannot be used lightly or for purposes
other than unveiling the elements of a particular offense: given their intrusion upon
individual liberties, the investigative means should be rigorously proportionate to
the legitimate ends. Coercive or intrusive action should be allowed only when and
insofar as it is strictly necessary to investigate a specific offense.
The principle of proportionality is often a component of the principle of legality
(in procedural law), according to which it is up to the law to set out the conditions
under which state authorities are allowed to take investigative measures. In many
cases, however, it also operates as an autonomous principle, respect for which by
the investigating authorities can be ensured by subsequent judicial review. This is,
for instance, the case with coercive measures (like pretrial detention) and, in some
countries, even with intrusive investigative measures (like interception of
communications): the person who suffered the deprivation of liberty or the intru-
sion can apply to a judicial authority in order to have the restriction scrutinized as to
its proportionality with the investigative need and the standard of human rights
protection.
Conclusion
In this chapter, we have identified some basic concepts of substantive and
procedural criminal laws. We have seen that at the outset of any discussion
regarding criminal law, a decision needs to be made as to which forms of154 J. Keiler et al.