Q: Texas home rule charter town can city completely change it's ordinances after a crime is committed to prosecute with new

A: In the United States, there is a fundamental legal principle known as the "Ex Post Facto Clause" found in Article 1, Section 9, Clause 3 and Section 10 of the U.S. Constitution. This clause prohibits the federal government and state governments from passing laws that retroactively change the legal consequences or status of actions that were committed before the enactment of the law.

The Ex Post Facto Clause applies to criminal laws, not to civil laws. Therefore, a city or town, even with a home rule charter, cannot change its ordinances after an alleged crime has been committed and then use those changes to prosecute or bring new criminal charges against a citizen for actions that occurred before the changes were made.

However, if the changes to the ordinances are civil in nature (e.g., changes to zoning laws or regulations), then the Ex Post Facto Clause may not apply. In such cases, it's possible that the new ordinances could be used in ongoing legal proceedings.

Regarding the specific case you mentioned about an attack by a dog under negligence in Coleman County, Texas, the prosecution would typically rely on the ordinances and laws that were in effect at the time of the alleged incident. Any changes to the ordinances after the fact should not be applied retroactively to criminally prosecute the case.

It's important to consult with a local attorney who specializes in municipal law and criminal defense for more specific guidance on your particular situation.