What to do when the standards conflict with the existing code

Before you begin work in any area, first take the time to understand the code you're working in first. Look around to see how it's architected, the libraries in use, etc. You will absolutely find existing code which conflicts with the stated coding standards. So how should you proceed?

Small Modifications, bug fixes, etc.

When making limited modifications to existing code, conformity is more important than the Standards. Many small modifications are made to our product. The ability of a new and existing developers to follow the code it is directly related to how consistent the code is. Stick to the Architecture and technologies existing in the area you're working with. If the project is architected using Factories, create a factory. If commons-io is used, use it instead of plain JDK. Don't introduce SLF4J logging if commons-logging is already in place.

New Development in existing area / Refactorings of Consequential Size

When the existing codebase does not conform to the standards and new development is of a great significance, diverging from the existing code may be warranted. This is completely subjective and situational. In these cases it's best to consult with your team members and the resident architect for that particular area (Link to Project/Architect matrix).