This sounds like union-busting to me.
I have a better idea, leave the collective bargaining agreements just as they are and pass laws which would dismiss criminal charges when the officer is found to be lying at any stage of the process.
This could involve an officer lying to potential witnesses, lying to a defendant in order to obtain a confession, lying during a trial and any other criminal act that may have been committed by the officer.
Not only would this serve to make the system more honest, but it would relieve jail overcrowding. After all, this country incarcerates more people as a percent of the population than any other nation in the world.
A few innocent people might be spared incarceration too. There have been numerous documentaries in the public media lately about innocent people being coerced into false confessions.
Union-busting is not the answer. Directly making the system more honest would be much more effective.