Legal Question in Criminal Law in California

Re: Meeting Your Accusers

You have the right to *confront* witnesses against you, not to "meet" them. Further, this right applies at trial, not at the time you interact with the police.

Most of the time the police officers' testimony will not be relevant to the prosecution. After all, the crimes with which the defendant is charged were probably complete before the police arrived. SWAT teams, however, tend to respond to hostage situations and other ongoing crimes. Their testimony is more likely to be relevant.

At any rate, the officers wear masks (which are usually clear) to protect them from physical danger, not to make them hard to identify. They would rarely have reason to deny their role in an operation, especially while testifying under penalty of perjury. Police reports and logs will also confirm who was present at the time and who did what.

Re: Meeting Your Accusers

I think your confusing the right of the accused to face witnesses against them at trial with the right you mentioned in your question. In a situation were the police are called in and the SWAT unit is required it is generally very dangerous and it calls for special needs in order to contain the situation. The right of the accused to face the witnesses against them is at trial and there are special circumstances where the right to face the accused is modified to protect the safety of the witness. The situation you have described in your question would not fall under the right of the accused to face witnesses against them.