It was Paris who had asked Juliet's hand in marriage. He was a young nobleman and kinsman to Prince Escalus, and he was also a conventional young lover who had wanted to marry Juliet earlier on. He had deceptively approached Lord Capulet about the chances of him marrying his daughter, trying to be persuasive to get good benefits from him. He tried to organise the wedding and forced Juliet to marry him, not knowing that she had no love feelings for him.
The nobleman Paris is sly and found his way into Lord Capulet's good books, who in turn pressures Juliet into marrying Paris after Tybalt's death.
Paris asks her dad (who has the most power). But Romeo asked Juliet herself (who has no power). ^-^ Yay Elizabethian Times.