Yes, some lawyers have a conscience. Like the “Saturday night massacre” a generation ago, Pres. Trump fired Sally Yates, the acting Attorney General because she refused to defend a questionable ban on travel for seven Moslem countries. See one description of the Saturday Night Massacre in 1973 here. Elliot Richardson and William Ruckleshaus refused to carry out what they believed was an unlawful order to fire Archibald Cox, the Watergate prosecutor. Ms. Yates refused to defend Pres. Trump’s ban on seven Moslem countries. She explained that she questioned whether that travel ban was lawful. See CBS news report.
The White House did not clear its ban with government agencies. It issued the ban with no prior coordination with the Department of Justice. The travel ban obviously surprised the Attorney General’s office. As Ms. Yates indicated, she had serious doubts about its legality and she wrestled with what to do over the weekend. She considered resigning rather than dealing with the problem, but she felt that leaving the office would just push the problem off on someone else.
Like 1973, this could portend further trouble for the president. When Nixon fired those two lawyers in 1973, that action very likely started his long journey toward eventual resignation. Firing the Attorney General and his first assistant was seen by many as unnecessary on Pres. Nixon’s part and clearly intended to protect himself. That was a shock to the country, just as today firing the acting Attorney General is quite surprising today. Ms. Yates is the only person at DOJ who is authorized to sign off on requests for warrants for foreign investigations. Her absence will surely cause further problems.