We have differing opinions about the word o'clock and the :00. Some of us were taught that o'clock should be transcribed as ":00" by those wonderful, hard-working teachers of our youth . Others of us go by the verbatim mantra: If a word was said, I transcribe it.
The problem is compounded by the English rules on how "times" should be transcribed: 4, 4:00, four. The formal English rules include each one as being correct under certain circumstances.
In our era of searchable documents and the removal of the need to "thumb through" every page to locate something, I believe we have to think differently about transcribing times. If the attorney is looking to verify what time the witness said something happened, then he is going to electronically search the document for a time. How does he do that if the time is expressed in varying ways? Think of what he would find if he is searching for "one" and uses the word.
For this reason, I recommend that all times that are on the hour be transcribed with the ":00" with no exceptions for what may have added to it. Then the attorney can always find a time he is searching for.
...arrived at 4:00...
...arrived at 4:00 P.M....
...arrived at 4:00 o'clock... (because he said the word)
Just an opinion.
Happy punctuating!
Margie