Is it possible that alcohol cause acne?

Unlikely: People tend to see cause-and-effect where there is none. The key is that all acne can be managed by evidence-based medicine nowadays. Alcohol is likely to exacerbate rosacea, which resembles acne somewhat. Red wine is infamous for doing this. Since this link is well-established and there's nothing similar in practice or theory for common acne, there's probably no effect.