Paul John Warren, 47, contested the charge of perverting justice in a half-day trial in the Supreme Court in Launceston on Wednesday.

The Crown had accused Mr Warren of having perverted justice on April 27, 2013 by sending a text message to Tracy Marshall which stated, "id get him 2 drop the charges or u r bothe f---" [sic].

It was part of the agreed facts that he had been charged with common assault against a man and had been due to face a hearing in the Launceston Magistrates Court on April 19, 2013, but the court ran out of time and the hearing was adjourned.

Ms Marshall had been summonsed as a witness for the hearing of common assault.

Crown prosecutor Virginia Jones called Ms Marshall to give evidence and she said she did not take the text messages lightly and saw them as a threat.

She read out the text messages sent to her by Mr Warren which included, "iv got a top lawyer so be careful whot u say... my lawyer is going 2 rip u 2 2 shred you be done for pershery" [sic].

Defence counsel Jarrod Van Arkadie said his client would not give or adduce evidence.

"It's probably the shortest case I have ever heard," Justice Stephen Estcourt told jurors before closing submissions.

Jurors returned a unanimous not guilty verdict after 40 minutes of deliberations.