washington president barack obama legal defense key initiatives include signature healthcare law collapse court put case hold president-elect donald trump hostile policies assume office jan. 20. pending conservative legal challenge could undo important elements obama presidential legacy trump expect opt defend obama policies court simply ditch initiatives attack since trump election nov. various court delay action three group case resolve obama leave office block administration regulation go effect another include challenge house representatives republicans important provision obamacare law case concern religious objections law mandate employers provide health insurance coverage birth control also include obama executive action put hold supreme court june spare deportation millions immigrants country illegally administration bid extend overtime protections workers republican-governed state like texas behind big challenge obama policies host case pending federal government due obama administration overreach say marc rylander spokesman texas attorney general ken paxton republican sue administration various issue include immigration rylander say texas officials continue pursue case look forward work new administration u.s. court appeal district columbia circuit monday put hold house republican obamacare challenge least feb. 21. trump republican congressional ally say plan repeal replace law mean case could become moot obama administration oppose delay case agree put hold effort revive obama 2014 immigration plan administration state challenge plan file joint motion nov. 18 say case put hold give change administration trump vow crack immigrants country illegally expect abandon obama block policy series case pending low court concern efforts christian group obtain exemption provision obamacare law require employers provide health insurance coverage contraceptives also hold pattern supreme court send case back low court may throw several rule favor administration low court await change administrations one case new orleans-based 5th u.s. circuit court appeal lawyers religious group say court paper delay afford newly-inaugurated president new administration opportunity take fresh look litigation consider potential resolutions acceptable side labor case federal judge nov. 22 prevent obama regulation extend mandatory overtime pay million salaried workers go effect dec. schedule give trump leeway change course take office far court delay action several case involve key obama policies include state industry challenge rule curb greenhouse gas emissions mainly coal-fired power plant appeal court washington hear oral arguments september yet issue rule trump say plan rescind regulation meanwhile supreme court agree decide major transgender right case hinge part obama administration policy position support female-born transgender high school student name gavin grimm identify male sue 2015 win right use school boys bathroom court yet schedule oral arguments case due rule end june u.s. court look ahead trump obama case fizzle