i was involve in an accident and they serch my vehicle from top to bottom is that legal?

The general rule is that 4th amendment requires the police to obtain a warrant prior to conducting a search.  However, the warrant requirement of the 4th amendment is subject to exceptions, especially within the context of motor vehicle searches.  In your instance, you do not provide enough facts to determine whether the search was conducted legally, however, the fact that you were in an accident may be probative of this issue.  Moreover, you should remember that consent is always an exception to the warrant requirement -- therefore, if you consented you would have no recourse.  Finally, you do not specify what, if any, negative consequences you suffered as a result of the search.  For example, did the police find contraband and arrest you?  If so, if the search was conducted illegally the evidence that resulted from the search may be subject to suppression. Or are you just interested in recovering for the pain and suffering associated with a possible illegal search?  Regardless of your injuries, I recommend that you consult with a skilled criminal defense attorney, who should be familiar with the law regarding motor vehicle searches in New Jersey, who can advise you with respect to the appropriate steps to take to protect your rights with respect to this matter.