Does the use of vulgar language in the workplace tend to increase sexual harassment?
Sexual harassment can have many definitions, which can be problematic both for lawyers and for those who are feeling uncomfortable at work but may feel that the behavior upsetting them is not "bad enough" to constitute sexual harassment. The use of vulgar, misogynistic, and rude language in the workplace, however, can certainly be considered sexual harassment, as it leads to an unproductive and unsupportive work environment, particularly for women.
Not all vulgar language constitutes sexual harassment necessarily. Some vulgar language does not have a sexual component, albeit it can still be inappropriate for workplace use and could still be classified as harassment or generating an uncomfortable workplace environment. However, the vast majority of vulgar language in English is connected to sex and sexuality in one way or another; certainly, much of it is misogynistic. The use of words like "screwed" in a business context—"they screwed us over"—would be considered mild by some, but has a misogynistic and vulgar overtone which paves the way for wider use of demeaning and inappropriate language. The use of profanity in the workplace can make coworkers, particularly women, feel uncomfortable and even unsafe; this need not be directly addressed to them, although vulgar comments about a woman's body or crude descriptions of sexual acts would certainly be classed as the pinnacle of sexual harassment through the use of vulgarity.
Even where things are meant to be "only jokes," attempts to be funny are no excuse for compromising someone else's comfort at work. Sexual harassment need not have a physical element to be very real.