First of all, you can't sanction opposing counsel, only the Court can "sanction. " Next, you don't "have" the preponderance of evidence.It may also apply to lawyers. Can you sue for medical malpractice in San Antonio without a lawyer? Yes, you are allowed to under the law. Call One of the Best San Antonio Medical Malpractice Lawyers. Generally speaking, in the US, an opposing attorney does not owe you a duty that would give rise to a claim for legal malpractice. On your behalf, they will investigate ethics violations, file new claims, file suit against former legal counsel if necessary, and seek to recover damages. When filing a lawsuit against your attorney, it is important to seek legal representation immediately. Find out how to sue for medical malpractice in Texas.