public class TestController : ApiController
{
    [HttpGet]
    public IEnumerable<Test> GetTests()
    {
        using(var context = new DatabaseContext())
        {
            return context.Tests.Where(w=>w.Enabled).ToList();
        }
    }
}

try
{
    using (var context = new DatabaseContext())
    {
        return context.Tests.Where(w=>w.Enabled).ToList();
    }
}
catch(Exception e)
{
    // TODO: handle also those ValidationErrors, thrown by Entity Framework
    // so here we get a lot more code
    _logger.Error(e);
}