The aide said Rep. Tom Graves (R-Ga.) is expected to question Genachowski on an apparently-lagging FCC probe into the infamous Google Wi-Fi data breach. The FCC probe was announced to great fanfare in November but has yet to produce any publicly available results.
During what privacy groups dubbed the "Wi-Spy" breach, Google collected and stored private data from unencrypted Wi-Fi networks, including passwords and e-mails.
The company has since apologized and boosted its privacy settings, persuading the Federal Trade Commission against fining it during a probe at that agency.
Genachowski, who is testifying Wednesday on the FCC budget, is also expected to take questions on whether the government should fund the implementation of net-neutrality rules. Republicans say the agency overstepped its authority when it passed the controversial rules last year.
Graves and Appropriations colleague Rep. Mario Diaz-Balart (R-Fla.), along with members of Energy and Commerce, led the charge to defund the rules.