possessives - "the police conspiracy" vs. "the police's conspiracy"

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  I am firmly convinced he is innocent and his accusation is the result of the police conspiracy.

  
  

  
  
  


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  I am firmly convinced he is innocent and his accusation is the result of the police's conspiracy.

  
  

  
  

Which sentence do you think is a better choice?

Answer

The question in the post is about possessive inflection and use of a compound word of noun-noun combination.

Genitive inflection or "'s" means possession/ownership/relationship/authorship or, to say it the other way round, one noun belongs to another noun for any, some or all of the above reasons. As

• cat's tail


• Lamb's essays.


• police's conspiracy.

In answering a question on the preference between a possessive or a compound noun Roger Woodham in 'BBC Learning English' writes that the link between two nouns can be established either by using possessive form or compound nouns. As

• The US Bank's Finance Division


• The US Bank Finance Division

Both are possible, but sometimes one form is more likely than another. For example, complemental noun groups can often be rephrased as compounds without "'s".

• the relativity theory.


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  the linguistics department.

  
  

  In a noun-noun combination of compound noun the first noun is more like a classifying adjective; it descrbes the nature of second noun. In news paper headlines or reports, such nouns summarize a lot of information at a stroke.

  
  


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  Watergate Scandal.

  
  
  

From the question it is not clear whether the police is the only perpetrator of the conspiracy or just a party to a multi-agency conspiracy which go by the name, Police Conspiracy.

If the police is only to blame for the conspiracy, POLICE'S CONSPIRACY has an edge over the other option. If we overlook niceties, both can do.