Compaore kom til magten i 1987 under et kup, hvor Sankara blev dræbt.
For første gang i mere end 27 år blev der i december valgt en ny præsident, da vælgerne gik til stemmeurnerne i det vestafrikanske land, som har modtaget så megen bistand fra Danmark.
Mr Compaore's ally, Gen Gilbert Diendere, was recently charged in connection with the killing, BBC online reports Monday.
Both men have denied any wrongdoing. Mr Compaore is in exile after being forced to resign last year.
Mr Sankara, a left-wing radical, is considered a hero for many Africans. The exact circumstances of his violent death have remained a mystery.
Remains thought to be those of Mr Sankara were exhumed (genopgravet) earlier this year. But a test carried out in a French laboratory found no usable DNA.
The result was handed on Monday to a judge who earlier this year ordered the exhumation of the corpse as part of an investigation mandated by the transitional government that took over from Mr Compaore.
Mr Sankara's family said recently that an autopsy (obduktion) has found that his body was "riddled with bullets".
During Mr Compaore's rule the investigation into the murder made little progress, BBC notes.
