Four Waterloo Region police officers pleaded guilty to 'discreditable conduct' charges at a hearing Thursday in connection with a drug investigation.

The charges were laid under the Police Services Act and are not criminal charges, but are connected to a larger investigation that does include criminal allegations.

Three of the officers pleaded guilty to watching other officers and civilians smoke marijuana without reporting it or doing anything to stop it.

As a result, Const. Amy Olson, Const. Chris Nielsen and Const. Brian Fox face financial penalties and will either have to give up vacation or work for free for a number of weeks.

The fourth officer, Const. Jason Gamble, pleaded guilty to the same activity, as well as smoking the marijuana himself.

He has been demoted from a first class constable to fourth class, which involves a drop in pay of more than $20,000.

Waterloo Regional Police Chief Matt Torigian says "I think the whole issue around drugs and what we're dealing with today is a re-affirmation that it's prevalent and that we can't let up, and we have to continue with our efforts in drug awareness and enforcement."

He also says it demonstrates the ill effects of drugs and how they can devastate someone's life.

Each of the four officers came forward with information against two other officers who face much more serious charges including possession, trafficking and theft of marijuana.

Those two officers face criminal charges in connection with the drug investigation and are due back in court on July 11 and August 11.