If you plead guilty to an offence you need to know and understand 3 things: 1. By pleading guilty you give up your right to a trial because you are ADMITTING the essential facts of the offence. YOU ARE ADMITTING GUILT. 2. Your plea must be voluntary – that is, it is YOUR choice. 3. When you plead guilty the decision of your sentence is up to the Judge and is not decided by your lawyer or the Crown Attorney. There are however steps your lawyer can take to ensure you do not get surprised by the sentence the Judge imposes.
Source: CanLII – 2015 ONCA 168 (CanLII)