Yes, a lawyer can appear against a former client, but only under strict conditions to maintain ethics and fairness. The lawyer must not use any confidential information learned from the former client in the new case. If the new matter is closely connected to the old case, or if using past information can harm the former client, the lawyer must refuse the brief.

A lawyer should appear against a former client only when the previous case is fully closed, interests are not related, and there is no risk of breaching trust. The advocate must ensure that the new case does not create a conflict of interest. Overall, appearing against a former client is allowed, but only when confidentiality, loyalty, and professional ethics remain completely protected.