A federal investigation of D.C. Mayor Vincent Gray did not find sufficient evidence to support but could not rule out corruption claims.

The Washington Post reported the ethics committee “found no direct evidence’ proving ex-District employee and former mayoral candidate Sulaimon Brown’s allegations that Gray’s campaign promised him a job if he verbally bash then-incumbent Mayor Adrian Fenty in last year’s election.

The criminal probe, launched in March, found indirect evidence pointing to the alleged promise, but was unable to firmly validate the claim, citing Brown’s “poor grasp of the facts”, according to The Washington Post.

In the eight month review, investigators have interviewed Gray’s staff, subpoenaed documents, including cell phone records, e-mails, and text messages between Brown and Gray’s campaign staff.

The report’s results resembled that of the D.C. Council this summer, which confirmed a top official in Gray’s campaign paid Brown to politically attack the former mayor, although Brown overstated the bribe. This probe did not find Gray directly involved with the incident, The Washington Post reported in August.

Gray has said he made no such deal and the Brown was only told he could have a job interview. Gray, an alumnus, has also repeatedly denied Brown’s claim that the Gray administration paid him thousands of dollars to stay in the race last November.

The report did not address the mayor’s campaign finance irregularities currently under federal scrutiny.

Brown was fired from his six-figure city job in March after local news outlets reported on his past legal troubles.