JC> Okay. I've seen this for years in cop movies, and what not. I've
 JC> asked several people that are in the legal community, but hadn't
 JC> asked any LEO's about this.
 JC> Is it legal to stop a car and commandeer it for police use?
Yes, it is legal. The officer and/or the City/State assume many 
responsibilities and liabilities when this is done. There must be reasonable 
grounds when this is done, and the request can be in the form of a lawful 
order by a police officer. The same would be true of other circumstances 
where an officer needed assistance from a citizen and there were reasonable 
grounds to indicate a duty on the citizen's part to provide that assistance.
Tom Rightmer - A Victims' Rights Advocate
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