If you are a Clerezza committer your votes are binding and you can veto any code modification with a qualified -1, see the Apache Voting Process for more information.
As the name suggests a committer has the right to commit changes to the repository. You may commit other people's as well as your own patches to trunk. You must only commit changes to trunk if these commits yield to an issue being closable and in the case that there has been no previous vote on the committed patch if you're ready to remove these commits in the event that they are not accepted (by lazy consensuns, or if someone asks for it in an explicit vote).
As a committer you may also create issue branches which allows you to commit unfinished work to the repository and others to comment on it. if you want to discuss a patch or ask for a vote on it instead of attaching it to the issue you would typically point to the issue branch in clerezza/issues.