Landowners fighting Bayou Bridge have fired back at the pipeline builders and challenged whether oil companies may seize private land generally, and whether Bayou Bridge in particular followed the law...Property owners filed new documents...that question whether oil companies may take land at all.  The Louisiana constitution allows gas pipeline builders to seize property under eminent domain, but only after a public hearing and upon receiving clearance from the state Department of Natural Resources, attorney Pam Spees, of the Center for Constitutional Rights, said in an interview.  However, there aren't any rules...for how oil pipelines are regulated when oil companies want to take land under eminent domain, she said...Some of the property owners have argued that Bayou Bridge construction crews entered their...plot without permission and before the eminent domain suit could be settled...[T]he litigants said that while many consented to allowing Bayou Bridge to run through their land, others did not...Energy Transfer Partners did not respond to a request for comment...Earlier...the pipeline company agreed to stay off the land until an expropriation hearing scheduled for Nov. 27.  However, a Bayou Bridge spokeswoman said the decision would not push back their planned October completion date.  The company has argued in court that Louisiana law permits common carriers of petroleum products to expropriate private land if they are acting as a public utility...