"In how many courts have you testified as an expert witness?"

But whether she will testify as a witness for the prosecution in cases yet to come trial is still a question.

He'd testified as a witness the day before, but he was here today on his own time.

I'm the only one who can testify as a witness.

Obviously your daughter won't have to testify as a witness now.

Hence the defense's threat to call the boy himself - he last testified in early March - as a witness.

The written summons called on her "to testify as a witness."

He has testified as an expert witness in state, federal, and military courts.

However, she may still be called to testify as a witness in the case.

And he can frequently be found testifying as a professional witness.