Considering Bias:  The Preston Deposition

What is the point of view of my source? 

This source gave me a lot of information, but how do I know what it says is true? To find out, I need to consider the bias of the source.

Just as I considered bias in the Boston Massacre poster,  I ask myself these questions as I think about a written document:

  • Who created the document?
  • Is there anything I know about the person that will help me understand the bias of the source?
  • Where was the person during the event?
  • Why did the person create this document?  Could  this person have anything to lose or gain? 
  • What are some key parts or words in the document that I think reveal the bias?

Who created the document?

  • This testimony is from the British captain of the troops at the Boston Massacre

Is there anything I know about the person that will help me understand the bias of the source?

  • I know that Preston was the officer in charge of the British troops the night of the Boston Massacre.  I also know that he was charged with murder because of the deaths of the Bostonians.  I expect his bias, then, to be to defending the British troops' actions and blaming the Boston crowd.


Where was the person during the event? 

  • Preston describes events at which he was not present--the fight at the ropeworks, the fight when the two soldiers were beaten, when the custom-house guard was surrounded--so he has no first-hand knowledge of these events


Why did the person create this document? Could this person have anything to lose or gain? 

  • Preston gave this deposition to explain his actions and to defend himself at his trial for the Boston Massacre. He has everything to lose if he does not do a good job defending himself--he could be hanged for murder!  Preston is defending himself and would want to make himself and his troops look blameless in his testimony.  


What are some key parts or words in the document that I think reveal the bias? 

  • words like 'obnoxious,' 'malicious,' 'cruel and horrid,' a 'mob' to describe the colonists, so shows his anti-townspeople bias

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Summary:
Historical inquiry process continues with:

  • Considering the bias of a source

 

Terry's Tips

Support students in evaluating bias

Help students recognize different ways to find bias in a source.  Make a check list (or work with students to make a check list), worksheet or graphic that helps them work through sources and ask key questions to evaluate bias.

For a lesson to support students' skills in evaluating perspective and bias, see Distinguishing Biased and Impartial Perspectives