Your wedding is your day. This is true whether you are the bride or the groom. You are sure to want for the day to be as special as possible. This is why you invest a lot of time in planning out every little detail. You pay a lot of attention to the flowers which will be used. You sit down for tastings of the food and cake which will be served. You even listen to all of the bands which want to play at your wedding. It is not unreasonable that you would put some consideration in to what your guests will wear when they show up to your wedding. While some do not feel comfortable telling other people what to wear, it is important to remember that this is your day and all requests should be met.
One time when it is mandatory that you request a dress code at the wedding is if you are getting married in special circumstances. For instance, if you are getting married on the beach, you might want to request casual attire. This is because the majority of beach weddings will not have the bride and groom wearing a full gown and tuxedo. Instead they might wear a nice dress and a light suit. If this is the case, you do not want people showing up at the wedding looking better than you do.
If you are getting married in a location which caters to luxury clients like royalty or the president, it would be disrespectful if anyone attending the wedding showed up in anything less than a tuxedo. Making your wedding a black tie affair is a great way to make sure that the pictures from the wedding will truly stand out. It is important to remember that in these occasions not everyone will be able to wear the required dress. You will have some people who will not be able to attend. While this is a shame, it is your special day and you deserve to get the respect you deserve.