The Salduz Act protects someone who is suspected and therefore interrogated. This law states that, as a suspect, you have the right to confidential prior consultation with a lawyer and the right to assistance by that lawyer during the interrogation.
Guaranteed or voluntary
As a suspect, you always have the right to prior confidential consultation with your lawyer and assistance during the interrogation. This means that you can talk freely about your case with your lawyer, without anyone watching or listening so certainly not the police. Just you and your lawyer. This always applies.
Are you suspected of offences punishable by a custodial sentence and were you arrested? Then you can also use this right and the police can call a lawyer for you (if you don't have one yourself) via the Salduz web application. A lawyer on duty will then do this consultation and exercise your assistance if you want.
As an adult suspect, you can waive this right. If you yourself feel that you do not need a lawyer, you can say so.
Minor suspects cannot waive this right, whatever the facts.