Sure it will. CBAs routinely put in place specific processes and hurdles companies have to go through to discipline and especially fire workers. This protects workers from exploitation and arbitrary disciplinary actions but it also makes disciplining those workers for legitimate ethical or even illegal reasons more difficult. In fact unions not only put processes in place, some of them will go as far as to provide legal representation to union members accused of criminal acts. Without the union these bad actors could just be fired.
Look at what happened at Volkswagon 10 years ago with the engines on Diesel vehicles that were programmed to fake emissions compliance. These cars spewed out 100 times the allowable pollutants. The company was fined Billions of dollars (not enough, but they were fined), top executives went to prison for fraud, even though some they claimed to not know about it. You know who got off scott free? The engineers who purposefully programmed the vehicles to cheat on the emissions test. Do you know why they got off? They were represented by a Union.
And that is just the union workers, before you consider the corruption that is regularly documented by Union leaders.
This has just not been my experience, working in an industry with a very strong, very involved union.
I've been involved with multiple disciplinary actions over the years, a few directly as a supervisor over the staff being disciplined, up to and including letting someone go. Where the union's involvement affected things was in the very rightful requirement of documentation of misdeeds and of prior attempts to correct the actions or behavior that they failed to deliver on when the misdeeds were not grounds for immediate firing.
There has been only one instance of a situation I had heard of where the union allegedly got in the way of a "legitimate" disciplinary action, when someone sought to fire a staffer due to a year's worth of significant errors and mistakes that did cause real damage. The union protected the staffer from being disciplined for that staffer's own errors and mistakes because ultimately it was the leadership team responsible for requiring that person to perform in an entirely different role and function that they were not hired for nor did they have the necessary technical skills to perform. And the documentation showed that leadership was made aware of that lack of training, of the likely consequences of putting an untrained staffer over that task, and it was the leadership team who gave inadequate time to get that training against recommendations.
What I
have seen get in the way of legitimate disciplinary actions is nepotism and cronyism within or including leadership teams. And I have seen union-enforced practices actively dismantle their ability to intervene in such a way, albeit imperfectly.
And just to add, regarding your Volkswagon example of a union protecting engineers who committed illegal acts, my understanding is that one, it was management who was ultimately responsible for both ordering the fraud take place and for hiding its existence, and two, the engineers
were prosecuted but the charges were dropped because of plea deals.