I'm not exactly sure that I know what you are looking for still. I would assume that the following statute is what your client is being charged under:
§ 18.2-119. Trespass after having been forbidden to do so; penalties.
If any person without authority of law goes upon or remains upon the lands, buildings or premises of another, or any portion or area thereof, after having been forbidden to do so, either orally or in writing, by the owner, lessee, custodian or other person lawfully in charge thereof, or after having been forbidden to do so by a sign or signs posted by such persons or by the holder of any easement or other right-of-way authorized by the instrument creating such interest to post such signs on such lands, structures, premises or portion or area thereof at a place or places where it or they may be reasonably seen, or if any person, whether he is the owner, tenant or otherwise entitled to the use of such land, building or premises, goes upon, or remains upon such land, building or premises after having been prohibited from doing so by a court of competent jurisdiction by an order issued pursuant to §§ 16.1-253, 16.1-253.1, 16.1-253.4, 16.1-278.2 through 16.1-278.6, 16.1-278.8, 16.1-278.14, 16.1-278.15, 16.1-279.1, 19.2-152.8, 19.2-152.9 or § 19.2-152.10 or an ex parte order issued pursuant to § 20-103, and after having been served with such order, he shall be guilty of a Class 1 misdemeanor. This section shall not be construed to affect in any way the provisions of §§ 18.2-132 through 18.2-136.
I would guess that the prosecutor's arguement will be that the men's room sign designated that portion of the premises as an area restricted to men only thus excluding your client from that portion of the premises.
If it were me I would likely argue that the sign does not meet the requirements of a "tresspassing" sign. However, I do not see a statutory definition of what constitutes a "No Tresspassing" sign. Perhaps case law has defined it?
Further, you could argue that construing the men's sign as a "No Tresspass" sign is overbroad (see the case at: http://www.law.umkc.edu/faculty/projects/ftrials/conlaw/virginiavhicks.html) although that arguement ultimately failed in that case.
If what you are really after is some terms that could be used to search such caselaw on lexis or westlaw then let me know and I will try to come up with some (or will opt out so that another expert can do so if I cannot come up with anything).
If that is the case it would be helpful to know what you've already tried. I will not however run any searches myself as the cost of doing so would be greater than the compensation that I would recieve from this site.
If I have answered your question, please click Accept. I am happy to answer reasonably related follow-up questions if you need further clarification.
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