In which cases/circumstances a Lawyer can/must renounce to the defense of a Client?

According to the Code of Ethics for Spanish Lawyers, the Lawyer has full freedom to accept or reject a case without any need to justify her/his decision.

The Lawyer may not, under any circumstances, accept orders/cases that are contrary to the interests of another Client whom she/he has defended or is currently defending.

Once the case had been accepted, the Lawyer may cease her/his intervention if irreconcilable discrepancies or insurmountable differences arise that affect and end up breaking the trust of the client-lawyer relationship or when circumstances arise that might affect her/his freedom and independence in the defense.

On the other hand, the Lawyer has to carry out the necessary acts to avoid the defenselessness of the Client in the case of resignation, informing the Court so that the Client can resort to the services of another professional.