The following code accomplishes what I need to do, though might not be the prettiest.
public List<string> ReturnMatchingMatters(IEnumerable<string> matterNames)
{
var filter = PredicateBuilder.True<tblMatter>();
filter = x => Sql.In(x.Matter, matterNames);
SqlExpressionVisitor<tblMatter> ev = OrmLiteConfig.DialectProvider.ExpressionVisitor<tblMatter>();
ev.Select("select Matter from tblmatter");
ev.Where(filter);
return this.dal.DB.GetList<string>(ev.ToSelectStatement());
}