This is going to continue to make me seem biased, but: Nova. Unless you REALLY want to work in DC, then you'd have to ask someone else. I think Villanova's regional rep. extends to NYC, and maybe to DC. CUA's reach is probably more local. In DC, I don't know how they compare.
So my advice is to go with Villanova.
Credited. Catholic is in the unenviable position of being well-known as the third worst law school in DC, and they don't even have the social justice/equal opportunity mission Howard and UDC have to justify themselves. Unless you're really, really into the idea of wording in government, and quite possibly in a job where your JD isn't actually applied to the practice of law, go to Villanova.
Also, Villanova's name alone carries a pretty disproportionate degree of layman prestige for the school's ranking. Like it or not, name recognition really does creep in on people's opinion of a school, and you're bound to see some preferential treatment from lawyers who did their undergrad there, too.
Most lay people I've talked to about Villanova have been surprised it's not ranked higher.