Assuming you're doing a typical full day interview loop pay attention to the first few interviewers, they're likely more of the junior employees. Ask them lots

Assuming you're doing a typical full day interview loop pay attention to the first few interviewers, they're likely more of the junior employees. Ask them lots of questions about the work environment, boss, etc. Obviously don't come out and ask 'is your boss an asshole?', have more subtle questions like 'what's the work/life balance like?'.