Jermain Defoe had denied both offences.
A footballer's sentencing for speeding in Essex has been adjourned after doubts were raised about paperwork in motoring cases in the county.
Jermain Defoe, 26, was due to be sentenced at Chelmsford Magistrates, but the case was put off until 10 July.
The England and Tottenham Hotspur striker was not present.
Essex Police are looking again at section 20 notices issued since March 2007 - they summon motorists to court for speeding and red-light offences.
Defoe's lawyer said he would argue that paperwork done by the police could be invalid on the grounds that it was handled by an unauthorised person.
A national newspaper claims thousands of speed camera convictions in Essex could be overturned because of the error.
Magistrates in Chelmsford found Defoe guilty at a hearing in May.
Investigation under way
They were told he twice broke a 50mph speed limit on the M11 at Chigwell in 2008.
Prosecutors said Mr Defoe drove at 65mph on 16 April and at 81mph in June.
Defoe, of Cuffley, Hertfordshire, denied any offence.
A spokesman for the Crown Prosecution Service (CPS) said the service had been informed by Essex Police there was a potential issue concerning the section 20 certificates that they provide.
"As a result CPS Essex launched an immediate investigation into the matter and asked the courts to adjourn all matters prosecuted by the CPS that rely on those certificates until the investigation is complete.
"As Jermain Defoe's case is one of those, we contacted his solicitor and an agreement was reached to adjourn the sentence hearing pending the outcome of the investigation."