The Right of Statement was a traditional Romulan privilege offered to a condemned state criminal prior to their execution. This allowed the accused to make a full statement explaining their actions and motives. There wis no regulation as to the content of the accused's statement.
In 2268, upon capture by the Romulans, Spock requested twenty minutes for his Right of Statement as a means to stall for time to allow for the installation of the stolen cloaking device. He was beamed aboard the USS Enterprise before he concluded his statement. (TOS: "The Enterprise Incident")