President Barack Obama's pick to head the Transportation Security Administration, Erroll Southers, withdrew his nomination Wednesday.

Southers, a top official with the Los Angeles Airport Police Department, said he is pulling out to keep the president's enemies from using him as a political lightning rod.

His decision comes as the government is investigating how terror suspect Umar Farouk Abdulmutallab was able to carry out a bombing attempt on a Detroit-bound Northwest Airlines on Christmas Day.

Obama selected Southers last September, but Sen. Jim DeMint, R-S.C., blocked his confirmation saying Southers would allow TSA members to form a union.

Southers also raised eyebrows when he provided inconsistent testimony to Congress regarding a reprimand that he received for running background checks on his then-estranged wife's boyfriend 20 years ago.

"I am not a politician. I'm a counter-terrorism expert," Southers said in a Wednesday interview with the Associated Press. "They took an apolitical person and politicized my career."