Passive-aggressive behaviour
Question # 1 What is passive-aggressive behaviour?
Passive aggressive behaviour is a deliberate and masked way to express anger.
It involves a variety of behaviours designed to get back at another person without the other recognizing the underlying anger. https://www.psychologytoday.com/blog/passive-aggressive-diaries/201601/6-steps-confront-passive-aggressive-behavior
Passive-aggressiveness is the indirect expression of hostility.
It can take the form of a negative attitude such as resentment. It can also manifest in resistance.
https://hbr.org/2016/01/reduce-passive-aggressive-behavior-on-your-team
The default mind-set at a passive-aggressive organization is defensiveness. People feel they need to “guard their turf.�
http://www.strategy-business.com/blog/Is-Your-Organization-Passive-Aggressive
Passive-aggressive behaviour develops in people’s minds
when they experience negative consequences of disagreeing, i.e. when they do not feel safe in the environment they work / live in.
https://hbr.org/2016/01/reduce-passive-aggressive-behavior-on-your-team
The passive-aggressive organization is insular, defensive, and rigid.
Resistance to change is rooted in its nature. http://www.strategy-business.com/blog/Is-Your-Organization-Passive-Aggressive
Further inspiration https://www.teacherspayteachers.com/Product/How-can-we-manage-our-emotions-1678947
Question # 2 How do we respond to passive-aggressive behaviour?
A large part of letting go of passive-aggressive behaviour is to accept that conflict happens.
http://www.fastcompany.com/3049996/hit-the-ground-running/how-to-eliminate-passive-aggressive-behavior-in-your-office https://hbr.org/2014/06/signs-youre-being-passive-aggressive/
Try to understand needs people have.
https://hbr.org/2014/06/signs-youre-being-passive-aggressive/
Focus on finding solutions, not faults.
http://www.strategy-business.com/blog/Is-Your-Organization-Passive-Aggressive
Commonly, passive-aggressive behaviour is expressed with sarcasm. Do not allow humour to shut things down. Say, “We’ve enjoyed a laugh, now let’s get back to Bob’s point.” https://hbr.org/2016/01/reduce-passive-aggressive-behavior-on-your-team
When someone comes up with a different point of view, try saying this: “That is a different way of looking at this issue. Interesting. What can we learn / gain from that perspective?” “That’s not how I was thinking about it. Can you explain why you think what you think, please?” Adapted from https://hbr.org/2016/01/reduce-passive-aggressive-behavior-on-your-team
Encourage openness, for example by  being open-minded yourself.  asking people to explain.
Adapted from http://www.strategy-business.com/blog/Is-Your-Organization-Passive-Aggressive
When a person’s body language is negative, ask the person this: “I can see you push away from the table. Can you explain why you do that, please?” https://hbr.org/2016/01/how-to-deal-with-a-passive-aggressive-colleague https://hbr.org/2016/01/reduce-passive-aggressive-behavior-on-your-team
Ask “How do you interpret the comment Susan made?�
https://hbr.org/2016/01/how-to-deal-with-a-passive-aggressive-colleague
Encourage people to focus on the benefits of addressing conflict directly. Examples of benefits Faster execution. Less gossiping. Fewer meetings. https://hbr.org/2016/01/reduce-passive-aggressive-behavior-on-your-team
Further inspiration https://www.teacherspayteachers.com/Product/How-can-we-manage-conflicts-2016263