How to Say "to doctor" in Spanish
The Spanish word for “to doctor” is “alterar” — C1 level.
English → SpanishC1
verbC1formal
manipulating data or results

Examples
Fue acusado de alterar documentos oficiales.
He was accused of tampering with official documents.
Es ilegal alterar el cuentakilómetros del coche.
It is illegal to doctor the car's odometer.
Alguien intentó alterar las pruebas del crimen.
Someone tried to tamper with the evidence of the crime.
The object of 'Alterar'
In this context, the thing being changed (the document, the evidence) is always the direct object of the action. You don't need a preposition like 'with' in Spanish.
Don't say 'con'
Mistake: “No alteres con los documentos.”
Correction: No alteres los documentos. In Spanish, you simply 'alter' the thing, you don't 'alter with' it.
Related Translations
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