A technical defense is one used by a defendant

Defendant

A defendant or defender is any party who is required to answer the complaint of a plaintiff or pursuer in a civil lawsuit before a court, or any party who has been formally charged or accused of violating a criminal statute...

 to seek acquittal based on the technicalities of the law. It is in contrast to a political defense

Political defense

A political defense is one used by a defendant that relies on political arguments for acquittal. The necessity defense can sometimes be used for this purpose, and shadow defenses are also sometimes used. In countries that have jury trials, the defendant may seek jury nullification....

 which seeks to use political arguments to persuade a jury

Jury

A jury is a sworn body of people convened to render an impartial verdict officially submitted to them by a court, or to set a penalty or judgment. Modern juries tend to be found in courts to ascertain the guilt, or lack thereof, in a crime. In Anglophone jurisdictions, the verdict may be guilty,...

 to nullify

Jury nullification

Jury nullification occurs in a trial when a jury reaches a verdict contrary to the judge's instructions as to the law.A jury verdict contrary to the letter of the law pertains only to the particular case before it; however, if a pattern of acquittals develops in response to repeated attempts to...

. Sometimes the desire to convince a jury on political and moral grounds is so strong that political defendants will reject a potent technical defense.