BANGKOK – Thai authorities have escalated their legal battle against the students leading pro-democracy protests, charging 12 of them with violating a harsh law against defaming the monarchy.News of the charges comes as the Thai capital Bangkok girded for another rally Wednesday as the students push their demands that Prime Minister Prayuth Chan-ocha and his government step down, the constitution be amended to make it more democratic, and the monarchy be reformed to be made more accountable.Police on Tuesday issued summonses for 12 protest leaders to answer charges of lese majeste, defaming or insulting key members of the royal family.