Halloween has become hugely popular in the last few years—more than 69% of people in the U.S. participate in some form or another. Halloween parties can also be a great way to inject a little fun into the office routine, and they let everyone show a little of their personality and creativity if costumes get involved. The majority of employees think that employer-hosted Halloween events are good morale boosters. Just make certain that you handle a few of the trickier aspects of this office treat with care to avoid a legal horror later. Use this as a guide.

Communicate potential pitfalls with costumes in advance.

If you want to allow costumes or even sponsor a costume contest for Halloween, that's fine—especially if you have a staff that tends toward the creative side. However, you need to make sure that employees know what type of costumes are acceptable for work and which ones aren't. You also need to make sure that your human resources department knows how to tactfully handle the situation if someone accidentally goes overboard.

Let your staff know that there are some basic guidelines to follow:

No religiously-themed costumes. Nuns, priests, and the Pope are common costumes, but they can offend those who embrace that religion. You should also be aware that you may have a Wiccan or Pagan in the office who considers green-faced witch costumes to be an affront to his or her religion, so put those on the list of unacceptable attire.

No politically-charged costumes. Particularly in an election year, when tensions are running at an all-time high among voters, you don't need the disruption.

No particularly sexy costumes. Anything with exaggerated sexual overtones (like the "sexy nurse" outfit) can lead to charges of sexual misconduct or encourage inappropriate behavior that could be construed as permitting a hostile work environment.

No racially-themed costumes. The "Indian chief" is as offensive to those of Native American ancestry as someone wearing blackface is to those of African-American lineage.

If an employee does come to work in a costume that's problematic, the person in charge of handling the issue needs to take a low-key approach. If an outfit is showing a little too much skin, a sweater might be an appropriate solution. Otherwise, simply ask the employee to go home and change and make it clear that there are no repercussions for an honest mistake.

Make it clear that participation is not mandatory.

While most people do view Halloween as a secular holiday, there are people who associate it with devil worship and Satanism. You need to stress to your employees that it is perfectly fine if they choose not to participate in any Halloween activities. Do not require employees to explain why they choose not to participate (because that is an unwarranted intrusion on their personal lives and religious beliefs), single them out in any way, or pressure them to participate. Just allow them to go about their work day as normal without negative attention toward them.

Keep a watch on employees with boundary issues.

You also need to be alert to any tensions that you have in the office if someone does feel strongly against the holiday because of their religious leanings and makes a vocal issue out of it. The employee who is anti-Halloween needs to be gently reminded that the workplace is not a place for religious discussion. Similarly, be on the watch for other employees who might take the opportunity to "prank" their non-celebrating co-worker and make it clear that such activity isn't acceptable. While you hopefully won't have to have this discussion with anyone, some employees do have a poor understanding of personal boundaries and you're likely to know who they are. If you do, a quiet word well in advance of the party might be wise.

Like all holiday celebrations that are worked into the office environment, there are precautions that need to be taken in order to keep your business out of legal trouble—but the chance to improve morale among your employees and create a few fond memories around work shouldn't be missed. For more information, contact local professionals like Caldwell Kennedy & Porter.