A case delayed by the USCIS for 5 years

Client married a US citizen in 2009, filed I-130 and I-485 in 2010.  USCIS delayed the adjudication for 5 years without a decision.  Client asked the USCIS many times without any positive response.

We asked client several times to file lawsuit against the USCIS.  Finally in may, 2015 client decided to sue the government.  We filed the lawsuit in May and within 2 weeks we receive interview notice;  within 5 days after the interview we received the approval notices.

Once again mandamus action is the best way to compel the USCIS to act.