A client asks a private investigator to 'hack' into their spouse's email account to find evidence of infidelity. How should the PI respond?

1. Suggest using publicly available tools to guess the password
2. Decline the request as hacking is illegal and unethical, constituting a criminal offense.
3. Explain that it is permissible if the spouse shared the password previously
4. Advise the client that hacking is only permissible with a court order